The Residence ending explained: Who killed AB Wynter?

Detective Cordelia Cupp (Uzo Aduba) inches closer to the show's culprit over eight madcap episodes, but the answers to this complex mystery are finally laid out for all to see in the feature-length finale.

In true Agatha Christie style, Cordelia gathers all of the key suspects from the White House staff to the President himself and his closest aides to a single room, where she proceeds to work through each of their conflicting stories.

The Residence fans will no doubt be eager to find out exactly who the culprit is in this elaborate mystery, so read on for our full guide to the season 1 finale – including the killer, their motive and method, plus what the future could hold.

The Residence ending explained: Who killed AB Wynter?

The Residence season finale reveals that the White House social secretary Lilly Schumacher (played by Molly Griggs) is the killer of AB Wynter.

The stunning reveal comes during a gathering of all the suspects in the White House's Yellow Room, where Cordelia Cupp gradually works through the convoluted stories of each one.

After a few misdirects, the maverick detective eventually settles on Lilly, shortly after the staffer attempts to pin the blame on innocent lovers Elsyie and Bruce.

On Lilly's motive, Cordelia explains: "She did it because she hates you, and by 'you' I do mean you, Mr President, but what I really mean is all of you: the house.

"Like, the actual house. The physical space. Have you seen what she's done with the blue room? You don't do these things unless you really hate this place."

She continued: "But also, like, the house as an idea. As an institution. She hates it: the history, the traditions, the staff, what it represents. America, I guess.

"She hates it and she hated Mr Wynter most of all because he represented what it represents and he was in her way and he had been for a long time."

Cordelia proceeds to outline how Lilly had wanted to completely reinvent the White House – even going so far as to tear it down from the inside.

However, her victim, AB, felt a great reverence for its traditional qualities and sought to see it preserved and celebrated for years to come in its original form.

He had also gathered evidence that Lilly was using her privileged position for nefarious purposes, including stealing and misappropriating government funds and trading in favours with her contractors and allies.

AB decided to report these misdeeds to the President in order to get Lilly kicked out of the White House for good, with the resulting scuffle seeing her rip out a page of his diary – that conveniently read like a suicide note.

That was what gave her the idea to murder AB that night and stage the scene as if he had taken his own life.

The plan initially went as she had imagined; Lilly lured AB to a private room for a 'reconciliatory' drink (laced with poison sourced from the greenhouse).

However, when AB realised that the drink had been spiked and stopped drinking, she had to go off-script, delivering the killing blow with an antique clock that she proceeded to hide in a maintenance passageway.

Lilly attempted to disguise her role in the grisly incident by impersonating the First Husband of the United States in a phone conversation with then-Assistant Usher Jasmine Haney, where she ordered that the passageway be sealed.

Ultimately though, Lilly would be just as confused as everybody else once the investigation got underway because AB's body was not discovered where she'd left it.

During the final interrogation, Cordelia revealed that the President's brother, Tripp, had dragged AB's body to another room as he briefly believed that he might have had something to do with the death while in a dazed and drunken stupor.

He felt that he couldn't come forward about moving the body any earlier, as he feared it would make him appear guilty of committing the actual murder.

What next for Cordelia Cupp after The Residence season 1 finale?

At the tail-end of the season, Cordelia visits the President of the United States' mother-in-law, who is residing in the White House too, and informs her that the killer has been identified.

Content with a job well done, Cordelia proceeds to get back to her primary hobby of birdwatching.

However, in the good graces of the President and Congress thanks to her dynamite detective work, it seems quite possible that she might be called upon again for another high-profile case.

For now, though, we'll just have to wait and see whether Netflix orders The Residence season 2.

The Residence is available to stream on Netflix. Sign up for Netflix from £5.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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