Young and athletic, London cycle courier Astrid Bell is bad luckfor other people. First she is knocked off her bike accidentally by her neighbour Peggy Farrell, who is found soon after, bludgeoned to death in an alley. Then, a few days later, Astrid is asked to pick up a package from a wealthy woman called Ingrid de Soto, only to find the client murdered in the hall of her luxurious home. For the police its more than coincidence. For Astrid and her six housemates its the beginning of a nightmare: suspicious glances, bitter accusations, fallings out, and a growing fear that the worst is yet to come. Because if its true that bad luck comes in threes, who will be the next to die?