We Finally Know Who Killed Elena Alves on The Undoing — Are You Surprised?

After weeks of being on the edge of our seats trying to figure out whodunit on HBO's The Undoing, we finally got our answer during Sunday's finale. Starring Nicole Kidman, Hugh Grant, and Matilda De Angelis, the six-part miniseries — based on Jean Hanff Korelitz's 2014 novel, You Should Have Known — follows a successful New York-based therapist named Grace Fraser, who suddenly finds herself engulfed in an investigation following the death of a young mother at her son's school named Elena Alves.

In You Should Have Known, Grace's husband, Jonathan, ends up being the killer after he confesses to her in a letter, and it looks like The Undoing stuck to a similar storyline as the book. Even though we already know who the killer is, check out all the other theories we had during the show ahead.

01
Did Jonathan Fraser Kill Elena Alves?
HBO

Did Jonathan Fraser Kill Elena Alves?

At first, it seems like a stretch to name Jonathan (Grant) as a suspect. He and Elena (Angelis) never interact in the first episode, and it appears the only reason he even knows about Elena is because Grace (Kidman) told him about her and pointed her out at the charity auction. However, it's worth noting that Jonathan did leave the charity auction shortly after Elena did after he supposedly got called into work. He didn't return home until late at night and was visibly shaken up when he did.

And after episode two, we now know why. As it turns out, Jonathan was secretly having an affair with Elena after he met her at the hospital he used to work at, and he even admitted to Grace that they fought and had sex on the night of her death, though he claims he didn't kill her. The episode ends before we learn anything else, other than the fact that he helped Miguel get into Reardon. However, by episode four, Jonathan confesses to knowing who the killer is, but it ends before he gets the chance to reveal their identity.

Turns out, the show decided to stick to the same storyline as the book, because during Sunday's finale, it's finally revealed that Jonathan is in fact the killer after Grace takes him down in court with the help of Sylvia (Lily Rabe). Almost immediately after Grace finishes taking the stand and leaves the courtroom, Haley (Noma Dumezweni) turns to Jonathan and tells him that it's his own fault that he got caught because he didn't get rid of the murder weapon. It's there and then that we learn that Jonathan did indeed kill Elena. Even though he tries to make a run for it by kidnapping Henry and attempting to jump off a bridge, he eventually changes his mind and ends up getting arrested.

02
Did Fernando Alves Kill His Wife, Elena?
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Did Fernando Alves Kill His Wife, Elena?

When someone is murdered, the first suspect is usually the spouse. Even though we only see Fernando (Ismael Cruz Córdova) for a few minutes in the first episode, his appearance is important. When Miguel (Edan Alexander) asks his dad where his mother is the night after the charity auction, he tells him she's working at her studio, but judging by his odd behavior, he seems to know more than he's letting on.

Prior to Elena's death, we never actually saw Fernando and Elena together, so it's difficult to tell what their relationship was like. However, Sylvia later tells Grace on the phone that Fernando and Elena were having marriage troubles, so that could have been motive enough.

But after that second episode, we're not so sure Fernando is the killer, after all. Even though he turned himself into the police, his whereabouts are later accounted for, and all the focus shifts to Jonathan.

03
Did Grace Fraser Kill Elena Alves?
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Did Grace Fraser Kill Elena Alves?

In episode one, Grace meets Elena for the first time during an auction committee meeting. From the very beginning, Elena seems particularly taken by Grace and she makes sure to let her know how much she appreciates her kindness. Their encounters are pretty brief, but Elena feels comfortable enough around Grace that she kisses her during their last meeting at the charity auction, which happens to be the night she's murdered. We don't really see a reason why Grace would have killed Elena, as she seems genuinely shocked when she finds out the news.

However, in episode three, Detective Mendoza (Édgar Ramírez) shows Grace a surveillance video that puts her at the scene of the crime around the same time Elena was killed. Grace remains adamant that she had nothing to do with Elena's murder, and it turns out, she wasn't lying.

04
Did Henry Fraser Kill Elena Alves?
HBO

Did Henry Fraser Kill Elena Alves?

After that major cliffhanger during the fifth episode, things aren't looking good for Henry (Noah Jupe). In the final moments, Grace ends up finding a hammer in Henry's bedroom that looks a lot like the missing murder weapon. Henry is shocked when he notices his mom's discovery, but could Henry actually be behind Elena's murder? I mean, he did recently confess to knowing about his dad's affair with Elena, so that does seem like a motive.

However, he also could just be covering for his dad. Given how close they are, it makes sense that Jonathan could have asked him to hide the murder weapon in his closet, since nobody would ever think to look there. It's later confirmed in the finale that he indeed was covering up for his dad and had nothing to do with Elena's murder.