Hank Harris (The Man in the High Castle) and Being Human alum Sam Witwer have signed on for recurring roles in ABC’s drama series Once Upon a Time.

Harris will play Nathaniel, a meek and troubled patient at a mental institution who finds himself trapped under the thumb of its evil and overbearing warden, Jacob (Witwer), who takes pleasure in tormenting his most disturbed and helpless patients.

The second half of Season 5 began with a mission to rescue Hook from the Underworld, a mission that turned out to be more difficult than expected as the heroes encountered souls with unfinished business.

Harris, repped by Global Artists Agency and the Coronel Group, most recently recurred on Amazon’s Man in the High Castle and WGN’s Salem. Witwer is repped by Gilbertson Entertainment and UTA.

Once Upon a Time, now in the second half of Season 5, was recently renewed for a sixth season.