Walled In is a 2007 Canadian horror-thriller film directed and co-written by Gilles Paquet-Brenner and starring Mischa Barton, Cameron Bright, and Deborah Kara Unger.

The film is based on the best-selling French novel Les Emmurés by Serge Brussolo.

Film opens with a little girl, Julie (Sophi Knight), wakes up to find herself in a small concealed room, confused at what is happening.

When the room starts filling with cement from all corners, the girl cries for her father, but the cement only continues to rise, and eventually she is buried alive through the film opens with a grim discovery: sixteen bodies are found entombed within the walls of the building where Julie met her tragic fate.

15 years later Samantha "Sam" Walczak (Mischa Barton) is a recent engineering graduate.

Sam arrives at the Malestrazza Building, and is greeted by Mary (Deborah Kara Unger), the caretaker.

Jimmy (Cameron Bright), the caretaker's teenage son, takes her bags to her apartment, previously owned by Julie, and explains the rules of the building: she is to stay off the eighth floor because it is Malestrazza's and the roof because it is too dangerous.

Sam researches the building and discovers that it was the scene of a horrible series of murders where sixteen people were entombed in the walls.

Jimmy takes Sam to the eighth floor and tells her how his father was one of the victims, the crime being blamed on a local factory worker.

Sam realizes from reading the journal that there must be a large, open space in the center of the building.

While trapped, Sam learns that Malestrazza orchestrated the murders as a form of human sacrifice, citing the fact that, of the Seven Wonders of the Ancient World, only the Great Pyramid of Giza is still standing after thousands of years, because (he believes) it was the only one in which workers were killed and buried during its construction.

When Jimmy brings her the medicine, she opens the capsules and starts creating a mix to try and blow out the wall to get into the garbage room.

At first she is infuriated with Jimmy as the hole was constructed for Malestrazza and no one else, but realizes Sam now knows too much and they must keep her trapped there as well in order to avoid arrest.

She eventually does kill him after some taunting, and he thanks her after he falls into his tomb and it begins to fill with cement.

[5] The film was rated 5/10 by IGN and had conflicting accounts of the performances of the cast, describing Barton as "terrific" and Bright as "wooden.