Final Curtain is a 1947 crime novel by the New Zealand author Ngaio Marsh, the fourteenth in her series of mysteries featuring Scotland Yard detective Roderick Alleyn.

The plot features the world of actors, and Alleyn's wife, the artist Agatha Troy, has a main role in the story.

[1] In 1946 England, with World War II finally ended, the painter Agatha Troy awaits, after a lengthy wartime separation, the return of her husband Roderick Alleyn, who has been chasing spies in New Zealand as his contribution, while Troy has been making maps and pictorial surveys for the army in London.

She accepts a commission to paint the celebrated actor Sir Henry Ancred at his ancestral home Ancreton Manor, where she meets his adult children and grandchildren, and witnesses the tensions and dynamics of a family of theatricals, who act as if on stage among themselves.

The main cause of trouble in the household is Sonia Orrincourt, a brassy young actress Sir Henry has made his mistress and then fiancée.

A series of practical jokes are judged by Sir Henry to be the work of his youngest granddaughter, Patricia, known as Panty, an outspoken, mischievous child currently attending a school evacuated to Ancreton during the war, where an outbreak of ringworm has happened.

Evelyn Banks reviewed the novel soon after publication, considering it keeps up Miss Marsh’s high standard, saying “The story moves smoothly, as do all Miss Marsh’s, to a satisfactory climax.”[1] The Observer considered it a “a detective story written with grace and culture, moving easily amongst well-observed characters.”[4] Marilyn Stasio, writing in The New York Times, titles a set of reviews as Final Curtain.