Fans particularly love it when the writers unravel the secrets the doctors keep as it always impacts the series in a major way. While some can be simple misunderstandings, others were quite life-altering and ended up affecting the relationships between the surgeons forever (and sometimes, it wasn’t even for the best).

Jackson and April’s Marriage

One of the biggest secrets some Grey’s characters kept was in season 10 that involved Jackson and April. After Jackson stands up at April’s wedding to Matthew, they run off together to Lake Tahoe and get married, keeping it a secret to everyone around them. When Jackson returns home one night from a board meeting at the hospital, he tells April that they won’t be able to keep it hidden much longer.

Jackson standing up at the wedding was shocking enough, and they gave everyone a surprise again when they revealed they were married. While their motivations to keep things private for a while and to be able to enjoy their marriage without everyone nosing in was fair, it did end up hurting Stephanie and Matthew, and inadvertently affected Jo and Alex’s relationship in the long run.

Arizona’s Affair

In season 9, Arizona and Callie’s tumultuous marriage comes to head when it’s revealed that Arizona cheated with Dr. Lauren Boswell (Hilarie Burton) in an on-call room after bonding over the patient they were both treating. Callie found out about the affair when she sees Arizona’s ring pinned to Lauren’s scrub shirt, despite Arizona’s intentions to keep it a secret.

It shocked audiences, as Callie and Arizona’s relationship had always been so strong. They were compatible and loving, and it’s likely that Arizona meant to hide it from Callie to protect her. However, this incident did end up affecting the couple in the long run and it destroyed the trust between them.

Izzie’s Child

In season 3, Izzie is faced with a secret from her past when her biological daughter, Hannah, is admitted to the hospital needing a bone marrow transplant. While the fans already knew that Izzie had a daughter, none of her friends did until George found out she was undergoing the procedure.

Considering how her colleagues reacted when they found out she had been a model and how people shamed her for her upbringing, it’s not surprising that Izzie felt like she had to keep this part of her life a secret. It must have felt like she needed to protect herself. The only people, as far as fans are aware, that know of this secret is George, Bailey, and Alex.

Owen’s Affair

After their own set of troubles, Cristina and Owen’s marriage began to crumble in season 8 when Owen cheated on her after she had an abortion. With Owen and Cristina’s relationship having been strained for weeks, the cardiothoracic surgeon soon began to suspect that her husband was keeping something from her and was possibly cheating. Owen had no intention of telling her what he was keeping a secret until she confronted him.

After everything they had been through, this was one of the most shocking secrets to ever be exposed on the show. Considering how much they loved one another, no one would have predicted that Owen would end up destroying this trust between them. It’s not surprising that it took them so long to recover after this.

George’s Affair

Season 3 delivered one of the biggest surprises of all when the writers decided to put George and Izzie together. After a night of excessive drinking, George and Izzie ended up having a one-night stand which eventually blossomed into something more. Since he had been married to Callie at the time, George had intended to keep this a secret. However, due to George and Izzie’s closeness, Callie began to suspect something more was going on between them.

Fans were irritated and disappointed that the show went this direction with George, as he was generally involved in some of the show’s sweetest moments and would always be honest about his feelings. To see him lie to Callie for weeks on end made fans lose respect for him.

The Alzheimer’s Trial

After Meredith and Derek begin an Alzheimer’s trial in season 8, she tampers with the dose that is to be given to Adele Webber. Since she could have lost her job and prohibited the hospital from creating any more clinical trials, Meredith decides to keep quiet. However, this eventually comes to light when Alex drunkenly confesses to Owen what she did, leading to the trial being disbanded and hopeful patients’ lives ruined in the process.

This ended up having repercussions for the other surgeons too. Not only was Meredith devastated by Alex’s betrayal but she also ended up kicking him out of her house. Her secretive actions also ended up affecting her relationship with Bailey and Derek, who were absolutely furious by her recklessness. Her decision even lost them custody of Zola for a while. Out of all the obstacles Meredith had to overcome on Grey’s Anatomy, this was one of the hardest.

Preston’s Hand

Towards the end of season 2 and into season 3, Dr. Preston Burke is shot in the shoulder on his way back to the hospital after securing a heart for a transplant patient. It left audiences clamoring for answers after the season cliffhanger.

The injury causes tremors in his hand that he and Cristina mask for months, wrapped up in a secret that is detrimental to their friendships, peer relationships, and their own romantic relationship for some time.

George is particularly upset, as this could have severely jeopardized the surgery his dad was to undergo later (until he requested Dr. Hahn). Fans were also surprised by the recklessness of it all, especially since Burke and Cristina were usually the most responsible surgeons of all. To place their pride above the patient’s well-being showed how selfish they could be too.

Izzie And The LVAD

In season 2 of Grey’s Anatomy, Izzie falls in love with her heart transplant patient and begins a desperate attempt to save his life before it’s too late. At some point, she decides that cutting his LVAD wire to bump him up the transplant list is the best way to achieve this, and she asks her fellow interns to keep the secret until she can figure out what to do next.

They all do, but not without major personal costs to themselves, especially in Izzie’s case. However, while keeping this a secret that was extremely reckless, it did show that they were extremely loyal to one another.

Derek’s Marriage

At the culmination of season 1 and into season 2, viewers bear witness to the most shocking secret Derek ever carried: being married to a woman back in New York. After his marriage to Addison dissolved because of her affair with best friend Mark, Derek flees to Seattle and meets Meredith, beginning a whirlwind romance and relationship.

When Addison shows up by the end, fans were left asking why: was it because he was overwhelmed at the process, and in denial, hoping it would just go away quietly? Was it because he wasn’t ready for divorce? Speculation continued for months afterwards of Derek’s intentions.