A Haunting in Venice ending explained: who is the killer?

 Riccardo Scamarcio, Camille Cottin, Jude Hill, Tina Fey, Kelly Reilly, Emma Laird, Ali Khan and Kyle Allen in A Haunting in Venice.

We have seen Hercule Poirot solve a murder on the Orient Express and a death on the Nile, but just how does the great detective find out who is the killer in A Haunting in Venice? Be advised, this is our A Haunting in Venice ending explained feature, so if you have not yet seen the movie, perhaps best to check back in when you do.

Kenneth Branagh stars in and directs A Haunting in Venice, his third outing with the iconic movie mustache of Agatha Christie's sleuth following 2017's Murder on the Orient Express and 2022's Death on the Nile. The new movie sees Poirot, retired and living in Venice, invited to a seance on Halloween. When someone ends up dead, Poirot must find the rational answer to the seemingly supernatural act.

Joining him is an all-star cast that includes Tina Fey, Michelle Yeoh, Kelly Reilly, Jamie Dornan, Riccardo Scamarcio, Camille Cottin, Jude Hill, Emma Laird, Kyle Allen and Ali Khan.

A Haunting in Venice is based on Christie's novel Hallowe’en Party, one that has not previously been adapted for the screen. So unlike Orient Express and Nile, which have had multiple adaptations, unless you've read Christie's novel, we've never been told who the killer is.

Final warning to stop reading if you have not had the chance to watch A Haunting in Venice and want to be surprised. Otherwise, let's break down the A Haunting in Venice ending.

What happens in A Haunting in Venice?

A seance scene in A Haunting in Venice
A seance scene in A Haunting in Venice

Hercule Poirot (Branagh) has made his home in Venice, Italy. He is retired from solving cases, though many Venetians seek his help, only to be stonewalled by his bodyguard (Scamarcio). That is until his old friend Ariadne Oliver (Fey) arrives.

Ariadne invites Poirot to a seance to see if he can figure out how the alleged psychic, Mrs. Reynolds (Michelle Yeoh), is stumping everyone. Reynolds has been hired by Rowena Drake, a famed opera singer who lost her daughter, Alicia, a year prior. She died from falling off their palazzo balcony, though some believe the death has supernatural implications, as the palazzo is said to be haunted.

In addition to Poirot, his bodyguard, Ariadne, Rowena and Mrs. Reynolds, attending the seance are the housekeeper Olga Seminoff (Cotton), Alicia's doctor Dr. Leslie Ferrier (Dornan) who suffers from PTSD and his son Leopold Ferrier (Hill), Mrs. Reynolds' assistant Desdemona Holland (Laird) and Alicia's ex-fiance, Maxime Gerard (Allen).

During the seance, Mrs. Reynolds, reveals Alicia was murdered by someone in the room, but it's not clear who. Poirot quickly finds a second assistant helping Mrs. Reynolds put on her performance, Nicholas Holland (Ali Khan), who was hiding in the chimney, though everyone else is spooked by what Mrs. Reynolds has done.

Poirot speaks with Mrs. Reynolds, who reveals she knows impossible details about Poirot considering this is the first time they met. As she plants these seeds of doubt into his head, she puts on the mask and cloak she wore when she arrived on Poirot, who then wanders a bit around the supposedly haunted palazzo. However, in those clothes, he is attacked by an unknown figure and left for dead, but saved by his bodyguard.

Just moments later, Mrs. Reynolds ends up dead, impaled on a statue. Convinced it is murder, Poirot begins his investigation. But, hearing voices and seeing things that should not be there, he struggles. Add in another seemingly unexplainable death of Dr. Ferrier while he was in a locked room, and one wonders if there is something supernatural at work, or if there is someone behind it all.

Who is the killer in A Haunting in Venice?

Kenneth Branagh in A Haunting in Venice
Kenneth Branagh in A Haunting in Venice

There are many compelling potential suspects in ex-fiance Maxime, devout Christian Olga, Mrs. Reynolds' assistants Desdemona and Nicholas Holland desperate to get to America and even Poirot's bodyguard, an ex-cop who retired after working Alicia Drake's death. However, it was actually Alicia's mother Rowena who was the killer. But why and how?

Poirot is able to deduce that Rowena, who was a single mother, did not like that Alicia was moving away from her with her engagement to Maxime. When Alicia returned after they broke off their engagement, Rowena made it so Alicia was reliant on her again. She put poison honey in Alicia's tea, which made her hear and see things. The honey came from the garden Rowena and Alicia had grown. However, Olga unwittingly gave her the tea as well, which caused Alicia to overdose, at which point Rowena staged Alicia's death, making it seem like a suicide caused by fears of the palazzo's ghosts.

Poirot realized the honey clue after he was accidentally exposed to it. He was given tea with honey that was found in a closet after he was attacked, as we learn by Rowena. Rowena had thought she had gotten rid of the tea, but it soon began to impact Poirot and cause him to hear and see things. When Ariadne uses some of the same honey to help clean a cut Maxime suffers, Maxime's comment that it's not normal honey gives Poirot the aha moment.

But why kill Reynolds and Dr. Ferrier?

The key to solving this part of the mystery is two comments from Rowena. The first being that she is nearly broke. Poirot figures out Rowena was being blackmailed by someone who realized she was responsible for poisoning Alicia. However, Rowena doesn't know who it is, but believes it's either Mrs. Reynolds or Dr. Ferrier. That is the why. The how is based on her saying the music room is soundproof.

Rowena's alibi was she was in the music room with Olga when Mrs. Reynolds died just after midnight. However, as the room was soundproof, Olga did not hear the bells ringing at midnight. Rowena set the clocks back in the music room, which allowed Olga to back up her alibi that they were together, despite the fact Rowena had thrown Mrs. Reynolds off the balcony and onto the statue minutes prior and hurried back to the room.

As for Dr. Ferrier, Rowena had a number of hidden phones inside the palazzo, which worked internally despite the ongoing storm impacting their ability to call out. Still suspecting he may be the blackmailer, she discreetly calls him and threatens to kill his son Leopold if he doesn't kill himself, which Ferrier does.

Rowena does not surrender to Poirot. She runs and is eventually chased to a balcony over the canal. During a flash of lightning, Poirot sees a figure floating in the night sky that lunges toward Rowena. Rowena then falls backward into the canal and drowns.

The police accept Poirot's conclusions, however, he does not reveal one detail. It was not Dr. Ferrier or Mrs. Reynolds who had blackmailed Rowena. Instead, it was Leopold. The bookish young man was able to catch the details that revealed Alicia had been poisoned. In the hope of being able to help his father, he blackmailed Rowena and received hefty amounts of money. He says he used some to pay his father's bills, but he does not know what to do with the rest. Poirot suggests he give it to Desdemona and Nicholas Holland to help them go to America.

Finally, Poirot, reinvigorated by the case, decides to end his retirement and begin to help others once again.