HBO miniseries The Undoing has been captivating viewers since it premiered in late October. The psychological thriller, which is based on the 2014 novel You Should Have Known by Jean Hanff Korelitz, tells the story of a seemingly perfect upper-class family whose lives get turned upside down following a terrible event. Veteran actor Hugh Grant plays Jonathan Fraser, a respected doctor working with children who have cancer and the incredibly accomplished Nicole Kidman his wife Grace Fraser, an equally respected and talented therapist. When an attractive young mother named Elena arrives on the scene, is brutally murdered, and news of an affair is revealed, the story becomes a classic whodunit.

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There are lots of twists and turns. And while Reddit is pretty popular for dolling out unpopular opinions about iconic shows, the site is also used for discussions on shows of all kinds. And some Reddit users have been discussing crazy theories about this show and what they think might happen in the end.

10 Grace Already Knew About The Affair

One keen-eyed viewer posted video of the scene when Grace meets with two clients, who are discussing the infidelity that caused them to seek counselling. The question posed to the partner who was unfaithful is if he thinks maybe he wanted to get caught.

In the scene, there’s an expression of recognition in her face as she asks the question and observes him avoid answering. It seems far too personal to her. The theory is that this scene was foreshadowing that Grace knew about the affair all along. Foreshadowing is a strategy often used in psychological thrillers and horror series these days.

9 Grace Is A Psychopath

When Grace goes to speak to Jonathan’s former colleague, the doctor implies that he believes Jonathan could potentially be a psychopath. But one Reddit user posits that perhaps this is all a red herring, and it could actually be Grace who is the psychopath.

The theory is that it’s all about one person who is tired of being so inherently “good” that they do something terrible to get a thrill. That terrible act could have been an affair by Jonathan, or maybe it’s actually murder by Grace.

8 Franklin Is A Psychopath

There seems to be far more to Grace’s wealthy father Franklin, played by veteran actor Donald Sutherland, than meets the eye. His emotional admission that he lent Jonathan half a million dollars almost seemed like it was an alibi more so than a confession. And his odd visits to the museum where he stares at a painting seem odd.

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The same Reddit user as above theorizes that maybe it isn’t even Grace who’s the psychopath, but rather her father.

7 Jonathan Is A Psychopath And Grace Knows It

Psychopaths can charm their way into normalcy, hiding their true identity with ease. So, it’s quite possible that Jonathan is a psychopath and has been able to hide it for a long time. One Reddit user suggests that Grace’s discussion with her son about Jonathan’s childhood dog could be hinting at this.

If Jonathan doesn’t want a dog because of this traumatic experience as a child, why wouldn’t he just tell his son? It’s entirely possible that his dog’s death wasn’t an accident at all. As big a question as this one, however, is whether Grace knows the truth or not.

6 Henry Did It

It seems implausible, but this is television, after all, so anything can happen. One Reddit user with an active imagination predicts that it’s Henry who did the deed and killed Elena. Their elaborate plot theory suggests that Jonathan and Elena were actually going to run away together, not break up.

Henry found out, went to confront Elena, and in a fit of rage, killed her. Even if Jonathan knows the truth, he would still take the fall for his son.

5 Grace And Elena Were Lovers

There does appear to be some sexual tension between Grace and Elena, as witnessed in the awkward gym scene when Elena approaches Grace completely naked and when they share a brief but tender kiss. One Reddit user thinks there was something going on.

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They suggest this based on the fact that Grace asks Fernando if there “were other men” specifically, not if Elena had affairs with anyone else. It’s as if she knows there were other women since she was one of them.

4 Sylvia Isn’t Real

This crazy theory suggests that Grace’s friend Sylvia isn’t a real person, after all, but rather a figment of Grace’s imagination, a coping mechanism to help her get through inner turmoil.

The evidence to support this theory, suggests the user, is the fact that Sylvia seems oddly unphased by everything that is going on, replying more practically than emotionally like a true best friend would. She also spends a lot of time focused on Grace’s life. Also, her comments after the group’s first meeting with Elena sounded like negative thoughts Grace might have been trying to supress. As per the series title, Grace participates in her own “undoing” by overcompensating for the flood of negativity and suggesting Elena was sweet, not weird or flaunting herself. Further supporting this theory is the conversation Grace has with Dr. Rosenfeld, where he blatantly calls Jonathan a psychopath while Grace vehemently defends her husband. That conversation alone seems unlikely to have happened in broad daylight, so it’s possible Dr. Rosenfeld isn’t real either.

3 Grace Witnessed The Murder

A lot of theories suggest that Grace is actually the guilty one, and she killed Elena. But others point to the possibility that maybe Grace was only caught on camera walking nearby the crime scene on the night of the murder because she witnessed the crime, not because she did it.

As a therapist, Grace knows all about repressed memories and blocking out traumatic events. It’s very possible she witnessed the murder, walked away in shock, and completely blocked out what she saw, convincing herself she wasn’t there and didn’t know what happened.

2 Sylvia Did It

Arguably the craziest theory of them all, and the least likely to be true, is that Sylvia is the one who killed Elena. Why? One Reddit user guesses that Sylvia was also having an affair with Jonathan and got jealous when she found out about Elana.

Or maybe Sylvia was having an affair with both Jonathan and Elena, via a three-way thing going on. It seems totally ridiculous but shows that fans are really getting creative as they try to predict what will happen in the end.

1 Franklin Doesn’t Exist

Further to the theory that Grace has created imaginary people, or has multiple personalities, to help her cope with things, one Reddit user goes a step further saying that not only is Sylvia is a manifestation of Grace’s hallucinations, but so is Franklin, her father.

Could Franklin be long gone but Grace stills sees him? The keen-eyed poster points to the scene when Grace is playing chess with her father. There’s also an iPad on the table with a chess game on it, so she could be playing online with a random person. It’s also noted that Henry doesn’t acknowledge his grandfather in any of the scenes, and the scene when Franklin asks Grace to “play the right hand” on the piano was another odd one. But the clincher? When “Franklin” stands outside Fernando’s house watching him and the baby through the window. Was that actually Grace, viewed in the form of this alternate personality of her dead father?

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