Grey's Anatomy: Izzie & Alex's Relationship Timeline, Explained (2024)

Izzie Stevens (Katherine Heigl) and Alex Karev's (Justin Chambers) complicated, long-term relationship is one of the most memorable love affairs in Grey's Anatomy. At first, their romance is unexpected, as they don't get along as interns at Seattle Grace Hospital, but the characters both come from broken homes and share a desire to become successful doctors. Grey's Anatomy is known for featuring characters who fall in love as a result of the proximity of working together, but there's something special and heartfelt about this particular couple. Their obstacles and arguments make up some of the most unforgettable moments in the long-running medical drama.

While the series largely focuses on Meredith Grey and Derek Shepherd's romance, Izzie and Alex have a significant love story as well. They separate for a large portion of the Grey's Anatomy timeline but do find their way back together. While Meredith (Ellen Pompeo) has to say goodbye to her soulmate Derek (Patrick Dempsey), Izzie and Alex eventually have a happy ending, although one that is just as emotional as the rest of their interactions.

Season 1, Episode 1, "A Hard Day's Night"

Izzie And Alex Meet As Interns

In the pilot episode of Grey's Anatomy, Izzie, Alex, Meredith, George O'Malley (T.R. Knight), and Cristina Yang (Sandra Oh) meet as interns. Most of the focus is on Meredith since the series is built around her character, and eventually, her family, hence the title. By extension, Cristina gets a focus since she is Meredith's "person." George, Izzie, and Alex, however, also get brief introductions in the pilot before their characters are expanded upon during the rest of the first season.

There is no indication that there are any sparks between Alex and Izzie. They both appear a little cold and focused on their new careers, and they don't take the time to get to know each other. This first impression is important as in a few episodes, Izzie and Alex will see each other in a different light, which will allow them to bond.

Season 1, Episodes 2-9

Izzie And Alex Focus On Their Internships, He Exposes Her Modeling Photos

In season 1, episode 2, "The First Cut is the Deepest," Izzie shows she can be a good doctor when she works on her first big case. Alex and Izzie don't interact much for a few episodes, but in episode 4, "No Man's Land," he reveals photos of Izzie as a lingerie model for Bethany Whisper to the hospital. Izzie shows her strength in being proud of making money to support herself through medical school while Alex realizes he shouldn't be so judgmental and immature.

The release of Izzie's photos by Alex isn't exactly a turning point for their characters, but it does plant the seeds of a connection between them as they both learn from the experience. Though Izzie and Alex continue to bicker during these episodes, Alex also starts to see Izzie's confidence in her abilities.

Season 2, Episodes 1-3

Alex And Izzie Bond And Work Together

In season 2, episode 1, "Raindrops Keep Falling on My Head," Alex and Izzie start flirting with each other. Their flirtations lead to them working better together as well. She helps him see that it's a smart idea to show patients more compassion instead of simply focusing on diagnoses. As Alex is concerned about a patient Joe (Steven W. Bailey), who comes in after suffering from an aneurysm, Izzie realizes that Alex is sweeter than she thought.

It's during this set of episodes in season 2 that Alex starts to become more than just the stereotypical big man on campus, allowing Izzie to get to know him a bit more. As they get to know one another, they begin to genuinely care about one another. The path to becoming one of the best Grey's Anatomy couples begins when the characters can no longer ignore their feelings for each other.

Season 2, Episode 4, "Deny, Deny Deny"

Alex And Izzie Have A Lackluster First Date

Although Izzie and Alex are both intelligent and ambitious people, which should give them enough in common to start a happy relationship, they have a tough first date in season 2, episode 4, "Deny, Deny, Deny." Izzie is angry that Alex decides not to kiss her at the end, but he proves his stubborn and secretive nature when he doesn't admit that he's upset about failing his board exam.

Though they both like one another, they aren't yet on the same page, or ready for a committed relationship. It's not unlike Meredith and Derek not being completely honest with one another during the early days of their relationship. The two of them aren't completely ready to be vulnerable and honest with one another. It still takes them a while to get to that point. While Izzie and Alex will learn to open up to each other, this is a rough point for them in Grey's Anatomy.

Season 2, Episodes 5-9

This is a turning point in Izzie and Alex's new relationship as she thinks that Alex doesn't have real feelings for her, and he is scared to be honest about what's going on. Alex is a fan-favorite Grey's Anatomy character because he realizes what he has done wrong and attempts to be a better person, and he knows that he has to explore his feelings for Izzie. Alex starts to grow quite a bit because of his relationship with Izzie and this is where that growth begins.

In season 2, episode 7, "Something To Think About" Alex becomes more courageous and kisses Izzie at Emerald City Bar. They kiss again at the hospital in season 2, episode 8, "Let It Be." The romance seems to be going well at this point in the series, though it doesn't progress particularly quickly just yet.

Season 2, Episode 10, "Much Too Much"

Alex Is Unfaithful And Sleeps With Olivia

While Alex appears to be growing up, he makes a mistake at the start of his burgeoning relationship with Izzie that creates a big setback for the two of them. He makes the mistake of sleeping with Nurse Olivia Harper (Sarah Utterback) as he's afraid of becoming too close to Izzie and having her reject him. He thinks by continuing to see other people, he won't feel as much for Izzie as he already does.

Izzie is understandably upset, and she and Alex appear to be over. However, since Grey's Anatomy is a drama where every couple breaks up and gets back together several times throughout their arc, it appears likely that the couple will find a way back to each other, even at this point in the series. Alex becomes a better Grey's Anatomy character after this intense plotline, as he knows that he was wrong and wants to be a loyal partner for Izzie.

Season 2, Episodes 11-20

Alex And Izzie Sleep Together But Remain Broken Up

Over the next few episodes of season 2, Alex and Izzie avoid each other at the hospital due to the hurt feelings and awkwardness that they're experiencing. They fall back on the same patterns that most of the couples in Grey's Anatomy do when they have a setback - avoidance and then hooking up before truly addressing their feelings. Most of their storylines are focused on the medical case of the week instead of each other.

In season 2, episode 16, "It's the End of the World", they are afraid when a patient comes in with a bomb in their chest and Izzie asks Alex if he will sleep with her since survival isn't guaranteed. That, however, doesn't mean that Izzie and Alex are back together. In season 2, episode 20, "Band-Aid Covers The Bullet Hole," Izzie has clear feelings for patient Denny Duquette (Jeffrey Dean Morgan), and she feels that she can move on from Alex.

Season 2, Episodes 21-27

Izzie And Denny Get Engaged And Denny Dies

When Izzie is assigned to Denny, there's an immediate connection between the two that makes her take a firm step away from Alex. Izzie and Denny have a passionate and whirlwind romance while he's stuck in the hospital that includes a proposal. Then, she cuts his LVAD wire to ensure he is given a heart quickly. Izzie's actions would have gotten someone fired from her position in the real world, but Izzie isn't fired, which is one of the most confusing Izzie plotlines on Grey's Anatomy as well as one of the darkest and most emotional.

Izzie risks her career for Denny and is devastated when he passes away from a stroke in season 2, episode 27, "Losing My Religion." Throughout the episode, the chief interrogates the interns, wanting to learn who really cut the wire, but it's not until after Denny dies that Izzie confesses. She feels like nothing else matters, and she quits her job (though it's not permanent) to save the chief from having to punish her.

Season 3, Episode 1-Season 4, Episode 17

Izzie And Alex Are In Other Relationships

Alex and Izzie remain broken up in seasons 3 and 4 of Grey's Anatomy as they develop feelings for other people. These separate relationships allow Izzie and Alex to grow as characters while they're apart from one another, allowing them to be more than simply a romantic pairing in the series.

In season 3, Izzie and George begin seeing each other, which is problematic since he is married to Callie Torres (Sara Ramirez). The relationship is a surprise for a lot of fans at the time since they hadn't had romantic leanings toward one another in the past. Alex falls in love with Rebecca Pope (Elizabeth Reaser), who is called Ava at first, and helps her come to terms with her accident, not remembering anything about her life, and her tough relationship with her husband Jeff (Jason London). Both Alex and Izzie become vulnerable with these other people, but something is missing, which eventually leads them back to each other.

Season 5, Episodes 1-6

Alex And Izzie Get Back Together And Alex Wonders If They Are Truly Committed

While Izzie and Denny are one of the best Grey's Anatomy couples due to their strong feelings for each other, Izzie genuinely cares about Alex as well, and the characters reunite at the beginning of season 5. They've had some distance from one another and been able to grow so that they can have a more meaningful relationship. They've both suffered heartbreak due to their experiences with Ava and Denny, and they've both come out the other side.

Izzie and Alex miss each other, and it's clear that the bond that they formed back in season 1 when discussing that they both had unstable homes and uncaring parents is still intact. When Alex asks if they are dating other people or just each other, this is a catalyst for their upcoming wedding, which allows them to finally commit.

Season 5, Episodes 7-21

Izzie Is Sick, And Her Relationship With Alex Is In Jeopardy

During the next few episodes of season 5, Izzie begins "seeing" Denny and feels that he is still around. Izzie hallucinates Denny because she is dying of cancer, and she has sex with him in her hallucination. She doesn't hide her visions from Alex though, which is a sign that the two are in a better place despite the circ*mstances, despite a lot of fans of the show hating this particular storyline.

This is scary and emotional for Alex, who is afraid of losing Izzie now that he has finally gotten her back, and Izzie is equally concerned about what is happening to her as she is diagnosed with Stage 4 metastatic melanoma. She feels a sense of peace when she is afraid of the path ahead of her, but remembers all the times that she comforted patients in the same position.

Season 5, Episode 22, "What A Difference A Day Makes"

Alex And Izzie Get Married

After finding out that she has cancer, Izzie also gets another surprise. Derek proposes to Meredith, and Meredith requests Izzie's help with her upcoming nuptials. While Izzie is sick and undergoing treatment, she distracts herself from her illness by helping Meredith plan her dream wedding. It gives something positive for Izzie to focus on and takes some stress off of Meredith. Meredith, however, makes a different decision for Izzie and Alex.

Meredith makes the kind gesture of allowing Alex and Izzie to get married on the day that she and Derek were planning to, with most of the plans that Izzie made for them intact, and this is one of the sweetest moments in the entire series. This Grey's Anatomy wedding episode is especially powerful since the "sickness and in health" vows are coming true at this very moment and Alex will be a support system for his sick wife.

Season 5, Episodes 23-Season 6, Episode 4

Izzie Has Surgery, And The Couple Moves Into Derek's Trailer

After Izzie chooses to have surgery to remove her tumor, Alex proves that he is more comfortable speaking about his emotions when he shows that he is afraid of his wife dying, but her surgery goes well. At the beginning of season 6, the couple begins their married life by living in the trailer that Derek owns, which results in a humorous storyline as a bear approaches Alex, and he is nervous and afraid.

This is a memorable part of the couple's long-term relationship that balances out the stress and sadness surrounding them. There's plenty of comedy in the two of them finally building a life together after avoiding their feelings for one another for so long in the show. At this point in the series, it looks like everything is going in a better direction for Izzie and Alex.

Season 6, Episode 5, "Invasion"

Izzie Is Fired And Leaves Seattle

While Izzie is considered one of the best Grey's Anatomy doctors as she is bold, confident, and natural, she also makes a lot of mistakes. Cutting Denny's LVAD wire isn't the only one, though it's certainly one of the most memorable. While that decision, and Denny's death, led to her quitting her job for a while, season 6 sees Izzie make another costly mistake - one that harms a patient.

At the start of season 6, she messes up a patient's dialysis, which ensures that she won't be able to receive a kidney, and Izzie loses her job because of the costly mistake. This mistake is also the catalyst for the end of her relationship with Alex, as instead of talking to her husband about what has happened and leaning on him for support, she breaks his heart and decides to leave Seattle where he has a growing career.

The decision seemed to come too quickly for fans, but it was largely due to the decision for Katherine Heigl to leave the series, and Izzie did get to come back to close out her storyline.

Season 6, Episodes 6-11

Alex Worries, Izzie Comes Back, And The Couple Has Problems

While Izzie is away, Alex has to pay for her time in the hospital during her cancer recovery, which emphasizes his responsible character and her impulsive behavior. Their roles have somewhat reversed compared to when they first began to connect in the first season of Grey's Anatomy. This is definitely a change from what the audience might have expected when they were first introduced to the characters, and it's one of the reasons Alex became such a fan-favorite. His growth is so much more evident than some of the other characters.

When Izzie comes back in season 6, episode 9, "New History," Alex has too much resentment to forgive her. This isn't just a rough patch for the two of them as Izzie left without a word and left Alex to take care of her debt. She can't simply make him understand. It's clear that Izzie and Alex are over at this point in the series.

Season 6, Episode 12, "I Like You So Much Better When You're Naked"

Alex Ends The Relationship With Izzie, And She Leaves For Good

Izzie leaves Grey's Anatomy in season 6 after attempting to fix her relationship with Alex. As much as she appears to desire to fix things, Alex cannot see a path forward. Alex shares his desire for a loving, compassionate, loyal person who he can count on and lets Izzie know that their love story is over because they haven't been able to be that for each other. Even though they clearly care about one another, loving one another isn't enough to make their relationship work, and right now, they cannot put in the effort required to do that.

What happens to Izzie next is left a mystery for several seasons, but it's clear that Alex has learned a lot about trusting people and making sure that his next partner isn't going to run whenever something goes wrong. While he doesn't rush into another relationship, Alex is able to understand what he wants, what he deserves, and how to put in the work.

Season 6, Episode 13-Season 12, Episode 2

Alex Moves On And Commits To Jo

Without Izzie, Alex initially focuses on his career. He develops feelings for fellow doctor Lucy Fields (Rachael Taylor) in season 7 and becomes closer to Meredith. In fact, he and Meredith really become one another's confidantes without Izzie and Cristina around. Alex slowly moves on with his life, no longer focusing on the pain Izzie caused him.

However, it's in season 9 that he falls in love with Jo Wilson (Camilla Luddington). The two doctors gradually develop their relationship and become serious in seasons 11 and 12. Jo and Alex have their own share of issues to deal with, most of which come from Jo having to process trauma from her own past, which she is able to do. Although it appears that Alex is happy and has met his true match with Jo, his past with Izzie is about to come back to haunt him in season 12.

Season 12, Episode 3, "I Choose You"

Jo Learns Alex And Izzie Could Have Children Together

Although Jo appears perfectly matched for Alex, she realizes that a relationship between her and Alex might not work out after all. Alex has been keeping a secret from her, and it's one that no one else has known about since he and Izzie initially got married. Jo discovers that Alex might be the father of Izzie's children when she finds out that Alex has been paying for embryos belonging to Izzie at a fertility clinic.

Izzie and Alex had decided to freeze embryos when she was sick, just in case anything went wrong with her treatment so that they could still have children in the future, something he hadn't told Jo. While Alex tries to remain calm and let Jo know that she should forget about it, Jo, who has had a hard life including an abusive marriage, is afraid of being left behind. The series hints at how Izzie could threaten Alex's new relationship at this point despite Izzie having been gone from the show for six years.

While for some fans, it might have seemed like a convenient way to throw a wrench into the relationship between Alex and Jo, it was a hint that Alex might not truly be as over Izzie as he believes himself to be. After all, he's still the one paying for the storage of the embryos.

Season 12, Episodes 4-Season 16, Episode 15

Alex And Jo Get Married And Have A Happy Relationship

Alex and Jo make up and continue their peaceful relationship through seasons 12 and 13. For multiple seasons, it appears that the tease about Izzie potentially having Alex's children is just forgotten. Alex and Jo are at such a good place in their relationship that they even get married in season 14, episode 24, "All Of Me." They have a good marriage, as Alex has become dependable in the years since Izzie moved away; he is now capable of being the stable partner that he always wanted to be.

Alex's relationship with Jo proves that the growth he experienced while in his relationship with Izzie wasn't going to be shortlived. His relationship with Izzie, even though it ended in heartbreak, made him a better person. It allowed him to be one of the characters to experience the most growth in the series and to have healthier approaches to the women in his life.

Season 16, Episode 16, "Leave A Light On"

Alex Learns Izzie Is Raising Their Kids And Moves To Be With Them

Alex and Izzie's unpopular final Grey's Anatomy storyline sees Alex phoning Izzie after penning a letter of recommendation for Meredith and remembering the happy times of the past. When he can hear children in the background, he learns that she is raising their twins Eli and Alexis. It's learning that he has a family that gives Alex pause. After reconnecting with Izzie and meeting his children, he makes a drastic decision about his life.

This major decision is, of course, influenced by the decision of Justin Chambers to leave Grey's Anatomy after playing Alex Karev for 16 years. Fans were sad to see him go, and the series wrote him out in a very abrupt way.

Meredith reads a letter Alex wrote her and learns he left Jo so that he could commit to Izzie. While Alex and Izzie are both happy about this decision, it was a bold move for the series, and the couple's happy ending is marred by Jo's heartbreak. After so many ups and downs, Izzie and Alex end up together off-screen in Grey's Anatomy while Jo is left to move on. It's unlikely that the series will ever bring back Izzie or Alex since both actors chose to walk away from the series and both characters had such drastic exits.

Grey's Anatomy

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A high-intensity medical drama which follows Meredith Grey and the team of doctors at Grey Sloan Memorial, who are faced with life-or-death decisions on a daily basis. They seek comfort from one another, and, at times, more than just friendship. Together they discover that neither medicine nor relationships can be defined in black and white.

Cast

Ellen Pompeo , Chandra Wilson , James Pickens Jr. , Justin Chambers , Kevin McKidd , Jesse Williams , camilla luddington , Patrick Dempsey , Sara Ramirez , Jessica Capshaw , Sandra Oh

Release Date

March 27, 2005

Seasons

21

Creator(s)

Shonda Rhimes , Michelle Lirtzman