The Flight Attendant’s Murder-Mystery Reveal Succeeds Where The Undoing’s Failed

Photo-Illustration: Vulture, HBO and HBO Max

The Flight Attendant and The Undoing are fundamentally different shows, especially where tone is concerned. While The Flight Attendant, which just concluded its first season on HBO Max, deals with some dark subjects, including alcoholism and criminal behavior, it doesn’t feel wrong to characterize it as a caper or describe it as fun. HBO’s The Undoing, on the other hand, is as serious as a frigid January morning. It is bracing and dramatic, the sort of series you watch with senses on high alert.

The two shows do overlap in one important way, though, aside from being members of the broader HBO family: Both of them center on a murder mystery and, throughout their respective episodes, attempt to keep the identity of the killer a secret until a climactic reveal in the last episode. Only one of them does this truly well, though. Hint: It’s not the one that stars the villains from the two Paddington films.

Within the opening minutes of both of these series, a dead body is discovered. In The Undoing, that body belongs to Elena Alves (Matilda De Angelis), a woman who was having an affair with Jonathan Fraser (Hugh Grant) and whose son attends the same school as Henry Fraser (Noah Jupe), son of Jonathan and Grace (Nicole Kidman). We know that Elena was brutally beaten, but initially, we don’t know for certain by whom. The attempt to figure that out is filtered through Grace, who appears to be in denial or oblivious to a lot of the things that have been happening in her marriage. There are shots of her eyes, darting and panic-stricken, that suggest maybe even she might have killed Elena and blocked the incident from her memory.

In The Flight Attendant, the deceased turns up in the bed of Cassie Bowden (Kaley Cuoco), a party-all-the-time employee of an international airline who hooked up with a passenger named Alex (Michiel Huisman) the night before in Bangkok, then awakens to find him still lying there, with his throat slashed. Once again, it is Cassie, a terribly confused woman, who provides our window into this world. That window can get pretty foggy, though, because Cassie is an alcoholic whose judgment is often far less than on point. She can’t remember much of the previous night. Which means, just as in The Undoing, we have reason to suspect our narrator, who is clearly not reliable and maybe, possibly, killed someone.

Both of these setups give way to TV seasons that are pretty plot-driven and that also diverge from their source material — both are based on novels — in significant ways. But The Undoing doesn’t have a complete handle on its identity to the same extent that The Flight Attendant does. In its first couple of episodes, The Undoing seems to be developing in the same mode as another HBO drama that was written by David E. Kelley, Big Little Lies, which also revolves around a crime that we don’t fully understand until the end of the season. But Big Little Lies is driven as much, if not more, by its sociological study of upper-crust Monterey and its deepening portraits of the women who live there.

The Undoing kinda tries to do something similar to that previous Kelley work, but it plays more like a juicy thriller that’s also trying to be a prestige drama because it doesn’t want to admit that it’s mostly just a juicy thriller. The Flight Attendant, on the other hand, has no qualms about admitting what it is: the TV show equivalent of a book you might pick up at the airport and get completely engrossed in during your flight. The series is all propulsive motion. There’s Cassie dashing away from that Bangkok hotel, and running through the airport to try to avoid being questioned, and popping into Alex’s office, and making a scene at his funeral. (Like Kidman in The Undoing, she engages in many of these activities while wearing fab coats and outfits, an added bonus.)

The subplots that involve other characters — including Cassie’s fellow flight attendant Megan (Rosie Perez), who is selling information from her husband’s computer to some nefarious types, and her best friend/attorney Annie (Zosia Mamet), also engaged in some sketchy activities on behalf of her firm — are filled with moments of suspense, too. There isn’t a dull or slow moment in The Flight Attendant. Not one. It helps, too, that Cassie is an extremely active unreliable narrator, as opposed to Grace, who is more passive, a mode that may have worked in You Should Have Known, the more introspective book on which it’s based, but doesn’t serve the TV thriller/courtroom drama that Kelley builds using that novel as a loose foundation.

As The Flight Attendant progresses, it does the kind of revealing character work that The Undoing pulls off less consistently. The surreal ongoing conversation that Cassie imagines having with Alex forces her to examine her shaky memories of other events, particularly from her childhood, a development that takes The Flight Attendant’s central gimmick — what happens when someone can’t remember how a death transpired and doesn’t know whether she caused it? — and turns it into a deeper, more consequential commentary on the heavy baggage children carry into adulthood. At first, you don’t necessarily expect The Flight Attendant to travel into such emotional territory, so it’s an inspired surprise when it does and actually makes it work.

Kathryn VanArendonk and I have already discussed the running of murder hammers through dishwashers and other things in The Undoing that demand too much suspension of disbelief. To be fair, plenty of bonkers things happen in The Flight Attendant, too. Cassie is constantly doing things that make no sense at all. If you’re afraid of being viewed as a murder suspect, why would you go to the murder victim’s office? Or break into his apartment? Or blab about a bunch of the dumb things you’ve done to the FBI? The difference is that The Flight Attendant owns its nonsensical plot developments. They are coded into the show’s DNA. Cassie is impetuous and self-involved and drunk at least 16 hours a day, so she’s prone to this sort of behavior, and Cuoco makes us believe she would make exactly this many ill-advised choices. It helps that Annie is constantly calling her on those bad decisions. That tells us the show knows it’s being unbelievable, as opposed to The Undoing, which goes in some wild directions with the straightest of faces and asks us to take what it’s doing seriously.

But what The Flight Attendant does most right is actually deliver a finale that is surprising. I won’t reveal the killer’s identity here, but I will say that it was not who I was expecting. There are a couple of other twists that blindside in a good way, too. These moments work because, as much as this series runs on a mystery engine, figuring out who murdered Alex is not the primary motivation to get to the end of the season. The Flight Attendant advances with such zip and takes such wicked delight in putting Cassie in dodgy situations that you hit play on each episode prepared to let the ride take you wherever it takes you. In other words: I didn’t care that much about who killed Alex because I wasn’t fixated on that. There were plenty of other things equally worthy of caring about.

The Undoing, on the other hand, eventually narrows its focus so fully onto the determination of the guilty party in Elena’s murder that its other, stronger elements — the terrific performances, the carefully curated sense of mood — come across as superfluous to the show rather than essential to it. By the last couple of episodes, the HBO drama has insisted that its audience be fixated out whodunit. When the answer turns out to be kind of an underwhelming drag, it winds up defining an experience that wasn’t all bad.

To put it more succinctly: While The Undoing closes with a chase and the odd liftoff of helicopters, The Flight Attendant efficiently and slyly does something much more gratifying: It lands all of its planes and leaves us hoping we can fly with it again, should a second season come to pass.

The Flight Attendant Finale Succeeds Where Undoing’s Failed