Its plot follows a young businesswoman who becomes trapped in an underground parking garage in midtown Manhattan on Christmas Eve, where she is pursued by a socially awkward, psychopathic security guard who is obsessed with her.

After receiving assistance from a socially awkward security guard named Thomas Barclay and turning down his offer to spend Christmas with him, she calls for a taxi and waits in the lobby.

Taking Angela to another level of the parking lot, Thomas reveals her co-worker Jim Harper tied to an office chair.

She hears a voice that appears to be an operator but later turns out to be Thomas, who delusively says that she will come around to love him back and flushes her out by flooding the elevator with a fire hose from a higher floor.

While hiding in the parking lot, Angela is tormented by Thomas, who declares he has no intention of letting her leave the garage and plays Elvis Presley's "Blue Christmas" over the intercom.

She breaks open an emergency fire axe and begins to destroy the cameras one by one while making her way to his office, prepared to fight.

Thomas sneaks up behind her, knocks her out with a taser, and hides her in the trunk of a car, just as two police officers arrive in response to a reported disturbance.

Thomas, now powerless and trapped, desperately starts pleading with her, saying he's always alone and begging her to give him a chance to be friends, but when Angela doesn't respond to his pleas, he angrily insults her, unwittingly exposing what he really thinks of her.

Finally free, Angela (who is now wet, bloody, and injured) opens the garage gate and limps out into a cold and desolate Manhattan Christmas morning just as the fire department, paramedics, and police can be heard arriving.

After completing the horror film High Tension (2003), director Alexandre Aja and his co-writer, Grégory Levasseur, began developing a new screenplay based on a series of real-life attacks on women in parking garages in Paris.

[3] Aja and Levasseur approached their friend, Franck Khalfoun, who had appeared in a small role in High Tension, to collaborate on the project, and ultimately, direct it.

[3] Commenting on the shoot, actress Rachel Nichols recalled: "This was definitely the most demanding job I ever had...  we shot for two months straight, working nights.

The website's critics consensus states: "P2 is full of gore, but low on suspense, featuring a cat-and-mouse plot has been done many times before.

"[13] Jeannette Catsoulis of The New York Times gave P2 a favorable review, though she likened it to an exploitation film, "bloody but not punishingly so, limiting the gore to tightly edited set pieces that never linger...

Throw in a car that won’t start, a creepy security guard and a filmmaking team with perfect synchronicity, and the result is a minimalist nightmare.