Astrid Bell has known most of her roommates for years, but while they have a history together - romantic pairings, one-night stands, friendships - each of them also has a past. Astrid is on her way home one day when her neighbor knocks her off her bike. Seeing she is bruised but not broken, her roommates help her home.

The next day, they learn that same neighbor was beaten to death hours later. Each of them tells the police what they know and are dismissed - until Astrid stumbles over another body. Two bodies in less than a week is more than just bad luck. As the line between attraction and danger blurs, the roommates must guard against becoming the killer's next victim.