"Heroes and Demons" is the 12th episode of the first season of the American science fiction television series Star Trek: Voyager. The episode first aired on the UPN network on April 24, 1995. It was directed by Les Landau and written by former Star Trek: The Next Generation story editor Naren Shankar. Set in the 24th century, the series follows the adventures of the Starfleet and Maquis crew of the starship USS Voyager after they were stranded in the Delta Quadrant far from the rest of the Federation. In this episode, after a sample of a protostar is brought on board, crewmen start to vanish from a holodeck simulation of Beowulf. The Doctor (Robert Picardo), a hologram, investigates and finds that a lifeform was transported to the ship alongside the sample. It escaped to the holodeck where