Jack Stillman, a rumpled 47-year old detective, is investigating a brutal series of stabbings in which the killer has left a note implicating Stillman's estranged brother, Michael. There is another reason to suspect Michael: At age 5 he was found holding a gun over his dead mother's body. Michael is brought in for questioning but soon, as the two brothers begin to rebuild their relationship, they join forces to track down the real killer. It's obvious that their prey knows Michael, but only after several suspects are killed one by one does it become apparent who the real predator is.