Joey Hopkins is a Locomotive Engineer and former Master-at-arms in the Navy. Jacob Russell is an undercover ATF agent and former Navy Seal. Their paths cross with tragic consequences when Joey is asked by a detective to help with an investigation. When the favor goes wrong, Joey kills Jacob in self-defense, not knowing that he is an undercover officer.

When Jacob reaches the outskirts of heaven, he is offered a deal. He can see his beloved wife again so long as he takes a position as a Guardian Angel. He accepts the job only to discover he must protect Joey, the man who killed him. To makes matters worse, Joey soon sustains a head injury to Jacob's delight. It backfires when Joey can suddenly see and hear his resentful Guardian Angel.

Jacob has his hands full as trouble always seems to follow Joey around. When Jacob requests that Joey save his wife, his troubles triple since she is wild and comes with a set of twins. Joey carries around his guilt while Jacob struggles to overcome his bitterness. Now, these two heroes must battle both evil and themselves as they learn to accept each other.