When a young father is executed, police learn the shooter may have been his close childhood friend. John helps track down the alleged killer, Diontae Whitson. Later, Cal's in pursuit of Louis Rojas, accused of murdering his ex-wife's new husband.

John goes after Eduardo Clemente, the prime suspect in his girlfriend's murder after her body turns up in the desert. Later, Cal's in North Carolina to hunt down Emigdio Ramirez Garcia, accused of ruthlessly murdering his wife in 1997.