When a mysterious black square appears in the middle of an apartment complex, suspicions develop between neighbors about the horrors it may bring. As mistrust grows, they slowly learn that the square isn't the only thing to be afraid of.

When Hayley accepts an invitation to spend Christmas with her sister’s new in-laws, her seemingly perfect holiday takes a turn when Paul, Hayley's brother-in-law's brother, unexpectedly shows up. Still harboring a grudge against Paul for ending her last relationship, Hayley reluctantly spends time with Paul and slowly realizes she may have been too quick a judge on Paul