"The Black Dog Runs At Night" is a song on the soundtrack of Twin Peaks: Fire Walk with Me. The song is composed by Angelo Badalamenti and performed by Thought Gang. The only lyrics in the song are "the black dog runs at night" which is repeated at regular intervals by David Lynch.
The song played for a few seconds in the scene when Leland Palmer pays Teresa Banks a visit. At the end of the scene, Leland walks away through a parking lot. Once Leland has left, Mrs. Tremond's grandson runs out from behind a bush and begins jumping around the parking lot, wearing a mask similar to the one worn by The Jumping Man.