Anne Royce McClain is a successful murder-mystery writer who lives on a New York estate, a mansion filled with priceless artwork (including pieces by former lovers) and a vast collection of her own first editions and manuscripts. She shares the house with her granddaughter Pamela Harrison, a childlike figure injured in the accident that killed Pamela’s parents, and Rashi, her Rajasthani factotum who doubles as an electronics wizard on parole. Anne moves about in a motorized wheelchair, sips cognac, and casually tosses still-lit cigarillos into wastepaper baskets, which set off the smoke alarms and wake the local fire chief at all hours. Beneath her eccentric surface, she remains a sharp, bestselling writer, constantly plotting new whodunits even as the household hums with danger and drama.
To celebrate her 64th birthday—and to hear that she is about to receive an Edgar Award—she invites her immediate family and her old friend and former lover Dr. Anthony Wainwright, who lives in Paris, to the mansion. The gathering becomes a tense tableau as Anne and Tony discover that her daughter-in-law, Sheila McClain, is scheming to seize control of the twenty‑plus‑million‑dollar estate through her husband, Anne’s weak-willed son Lawrence McClain, by having Anne committed and Pamela institutionalized. Pamela’s husband, Mark Harrison, is having an affair with Sheila and is in on the scheme. Anne records their revelatory conversation, preserving the truth for the moment when it might matter most.
Sheila learns that the tape exists and vows to have Anne “put away”; she sneaks back from a performance to steal the tape from the library, but falls victim to an elaborate garage trap—the prototype for Anne’s latest whodunit. Mark learns of the tape from Sheila before her death and tries to steal it, then bullies and blackmails Anne into selling her art collection so he can claim “his” share of the estate. Instead, Anne triggers the smoke alarm; with the household assembled, she declares that she will donate her art collection to the MoMA and leave the house to a local historical society, and will draw up the papers in the morning.
When Mark tests her, she reaches for the phone, and Mark snatches the envelope from her hand and dashes out of the room. The furor dies down, most people head back to bed, and Anne and Tony are left alone in the library. Anne reveals that she can actually walk: “Well, I like the image of a helpless old woman, everybody dancing attendance and kissing her behind.” She describes how “she” committed Sheila’s murder, ending with, “That’s exactly how you did it, isn’t it, Doc.” Tony admits that he did, that he has loved Anne for 40 years and would do anything to protect her and Pamela. For Pamela’s sake, Anne offers Mark a hefty envelope of cash and time to catch a scheduled flight to Australia before calling the police, and the two choose to stay together as the pair resume their game of chess. As the smoke alarm goes off again, the couple’s quiet vigil resumes, blending love, danger, and a lifelong partnership in a tangled, suspenseful finale.
