The CSI team is called to help when Karen Mathews reports her son, Jesse, missing from a playground where he was playing on the swings. Witnesses report seeing a man with a blue baseball cap near the swings. Clues in the park bathroom include blood and the boy's underpants. The boy is eventually found in a store, accompanied by a woman with a man fitting the earlier description. But the couple with the boy claim that he is their son Adam, while Karen insists he is her missing son Jesse.