Dean and Sam in Season Five, Episode 16: "Dark Side of the Moon"
The Winchesters do a lot of things together: track down supernatural baddies, ride in the Impala, and even get shot to death by a pair of angry hunters. But not to worry, their souls make it to Heaven where they relive pleasant memories from Earth. However, they're quickly sent on a mission to track down an angel named Joshua, whom God regularly contacts. Spoiler alert: They eventually get sent back to Earth to continue their misadventures in demon hunting.
