William Knifeman appears in Reservation Dogs, the FX on Hulu comedy drama that premiered in 2021 and was created by Sterlin Harjo and Taika Waititi. Played by Dallas Goldtooth, he is a spirit guide who visits Bear Smallhill with lessons drawn from his past life as a warrior. His solemn, rambling monologues became a fan favourite part of the show, and short clips of his advice were later shared as reaction sounds for moments that need mock serious wisdom instead of a real answer.