Confined to an asylum for the criminally insane, Nica Pierce is convinced that she, not Chucky, murdered her entire family. But when the psychiatrist introduces a new therapeutic "Good Guy" doll with a familiar face, a string of new, grisly deaths leads Nica to wonder if she isn't crazy after all.

After the passing of her mother, Nica Pierce, a young woman in a wheelchair, is forced to deal with her sister, brother-in-law, niece and their nanny as they say their goodbyes to mother. But when people start turning up dead, Nica discovers the culprit might be a strange doll she received a few days earlier.

Following his discharge from the US Navy after WWII, Freddie Quell is having difficulties adjusting to non-military life partly due to his war experiences in the tropics. He has a violent temper. He is obsessed with sex, which is partly why he can't and won't commit to his teenaged girlfriend, Doris Solstad. And he is an alcoholic, drinking primarily concoctions he creates himself with dangerous ingredients. It is these factors in combination that lead to him being fired from one job after another, from department store portrait photographer to cabbage picker. Wandering one night in 1950 while drunk, he stumbles upon a yacht being used by Lancaster and Peggy Dodd, the yacht aboard which their daughter Elizabeth will get married. Feeling a connection to the stranger, Lancaster invites Freddie to stay aboard to work. In addition to that work, Lancaster indoctrinates him into his cult, named the Cause, which purports to do things as varied as cure serious maladies and create world peace. Peggy, Elizabeth and Elizabeth's husband Clark all subscribe to and support Lancaster's teachings. The only one of the Dodd family that doesn't is Lancaster and Peggy's son, Val Dodd, who believes his father is just making things up as he goes along. Because of being lost psychologically, Freddie is easy prey, he who is looking for something or someone to guide him to a higher plane. But as Freddie travels with the Dodd family as they spout the gospel, he and the Dodds may become at odds with each other if Freddie cannot or does not find from them and the Cause what he needs in life to survive emotionally.

Armed with only one word, Tenet, and fighting for the survival of the entire world, a Protagonist journeys through a twilight world of international espionage on a mission that will unfold in something beyond real time.

Chucky returns to terrorize his human victim, Nica. Meanwhile, the killer doll has some scores to settle with his old enemies, with the help of his former wife.

After her mother's mysterious death, Nica begins to suspect that the talking, red-haired doll her visiting niece has been playing with may be the key to recent bloodshed and chaos.