Stars Daisy Lowe, Eliza Bennett, Alfie Allen. Directed and written by Tobias Tobbell. 90 minutes. Critic’s grade: C

Four people enter a London apartment. Two survive. There will be blood.

“Confine,” a low-budget British thriller shown at the recent Sunscreen Film Festival in St. Petersburg, is built on an appealing premise: Pippa (Daisy Lowe), a former model, physically and emotionally damaged in a car crash, is forced to survive by her wits when she faces an unwelcome visitor, Kayleigh (Eliza Bennett), a sexy, cunning crook seeking a temporary hideout.

Director Tobias Tobbell effectively makes use of the confined space, as the intruder and her inadvertent victim dance their way through a script that has Pippa reveal much about her insecurities — she’s agoraphobic, and something of a compulsive, well-organized neatnik hoarder, too. She’s also burdened, to some degree, with a twin, Edwina (Lowe), who continues to enjoy the celebrity spotlight once shared by both sisters.

Tobbell, also to his credit, elicits strong performances from his tiny cast, including Alfie Allen (“Game of “Thrones”) as a rather pitiable member of Kayleigh’s gang.

During the early scenes, the mercurial Kayleigh, she of the trenchcoats and wigs, begins to reveal her dangerous instability, and the claustrophobic environs furnish an uncomfortable edginess. Unfortunately, those sequences give way to later passages that feel like letdowns. The air begins to seep out of the story, and the denouement is largely unsatisfying. About those bullets …

Ultimately, the well-photographed production feels almost like filmed theater, which is potentially where these performances — particularly Bennett’s bracing turn as a high-strung, unpredictable young criminal — really may belong.