Only Murders in the Building season 3 ending: Who was the killer?

Now that the 10 episodes are done, it's safe to say that Mabel (Selena Gomez), Charles (Steve Martin) and Oliver (Martin Short) faced their toughest case yet, as they were dealt some tricky cards throughout the season - not least the fact that their friendship really took its own test.

Yet, tied by their love of true crime, the trio finally solved the case... even if it did mean tearing apart a loving mother and son.

But just who killed Ben, and was the same person that poisoned him in his Broadway dressing room the same person to push him down the elevator shaft?

Read on for a full breakdown of the ending of Only Murders in the Building season 3.

Only Murders in the Building season 3 ending: Who was the killer?

Well, as fans may have guessed as the episodes went on, there were two different people involved when it came to Ben's eventual demise.

If you cast your mind back to the first episode, Ben dropped down on stage after being poisoned, and we find out in the finale that it wasn't Loretta (Meryl Streep) or her son Dickie (Jeremy Shamas), after all. Actually, another mother and son duo were at the heart of the crime.

When the trio start piecing together the timeline of Ben's movements before his stage debut, they realise that the mysterious tape of him talking to someone in his dressing room was actually him talking to another nemesis in his life – a Schmackary's cookie.

But how did the cookie get poisoned? Well, having a feeling that Ben would eventually eat it, Donna (Linda Emond) sprinkled rat poison on the cookie after spotting a box of it in the stage manager's office. She locked herself in there to read the first review of her son's play, which was overwhelmingly negative, to say the least.

She put the review in the shredder, but it ultimately put the blame on Ben as the lead and Donna didn't want her son's first play to be panned on account of Hollywood actor Ben.

When questioned by the trio in the finale, Donna reveals that she has stage four lung cancer, hence why Loretta heard her being sick in the toilets on the night in question.

While Donna admits to poisoning Ben, she tells the trio that she didn't push him down the shaft of the lift, leaving the question of who the real killer is wide open. She asks if she can inform her son and the police after the opening night of the play, to allow her the chance to see her son's play to finally have its time to shine.

The trio agree, and the last-minute departure of Matthew Broderick sees Oliver take on the role of the lead detective himself. But while Mabel is watching her best friends on stage, she spies Donna and Cliff (Wesley Taylor) getting into a heated discussion, with him leaving his seat.

Read more

• Only Murders in the Building age rating: Is it suitable for children?
• Will there be an Only Murders in the Building season 4?

Mabel goes to follow him backstage, and when she finds him, he starts to recount memories of watching his mother's shows as a boy. Mabel tells him that Donna confessed to killing Ben, but she then realises that Cliff actually had her handkerchief, meaning that it was him who was the one at the elevator with Ben.

We then get a flashback showing that Ben received the news that he was poisoned, and when Cliff walks out of Oliver's party, the pair get into a heated discussion once Ben tells Cliff he was given rat poison.

As he's thinking back to what he ate, he tells Cliff he was fasting all day but only ate the cookie that Cliff brought in for the actors.

But Cliff tells Ben that his mother actually brought in the cookies, and when recounting his last meeting with Donna before he went on stage, Ben starts to realise it's Donna who poisoned him.

At the same time, Cliff has a flashback to the night in question, as he sees his mother acting suspiciously, walking in the direction of Ben's dressing room.

Ben tells Cliff he's going to call the police, but refers to Cliff as "boy", prompting Cliff to admit he's never liked Ben or wanted him in his play. The two get into a fight, and Cliff accidentally pushes Ben down the lift. In the present, he has a hallucination, seeing Ben on stage with Loretta, and then says he can't let his mother take the fall.

Hanging off the top of the stage's rafters, Cliff then threatens to Mabel that he'll jump, and Charles then sneaks up the stairs to help. Cliff is hanging off the ledge, but his mother comes up to give him her hand and help him up.

The cast take a bow, and after the play is over, we see Cliff and Donna arrested by the police and led to police cars.

Who died in the Only Murders in the Building finale?

Although things seem to be looking up for the rest of the final episode, if you've tuned into Only Murders in the Building, you'll know twists continue right up until the last minute.

Well, in this finale, someone met their unexpected end – but it could've very well been intended for someone else.

Charles's stunt double and fried Sazz (Jane Lynch) surprises Charles, Mabel and Oliver at the opening night party back at the Arconia, and everyone's happy to see her. She tells Charles that she needs to discuss something "sensitive" with him, but they agree to talk about it later.

Charles then announces that he's going to go and fetch a bottle of wine that he's been saving. He gets a text from Joy, which he interprets as romantic - but the rest of the group thinks otherwise.

The next scene is of a figure that looks a lot like Charles going into his apartment, probably to get the wine. But when they walk inside the dark flat, they're shot through the window – but we see that it's not Charles, it's actually Sazz.

Charles tells his friends that Sazz went to go and get the wine for him, but as the dramatic music builds, we see Sazz struggling for breath on Charles's floor.

With her hand covered in blood, the last thing we see is her making some kind of sign using the blood on the floor – could she be writing a message about her killer? We'll have to wait and see.

Only Murders in the Building season 3 is available to stream on Disney Plus. Sign up to Disney Plus for £7.99 a month or £79.90 for a year.

Check out more of our Comedy coverage or visit our TV Guide to see what's on tonight.

Try Radio Times magazine today and get 10 issues for only £10, PLUS a £10 John Lewis and Partners voucher delivered to your home – subscribe now. For more from the biggest stars in TV, listen to The Radio Times Podcast.