(written from a Production point of view)
Harry Young is the actor who appeared as a science division officer in several episodes of Star Trek: The Next Generation. As a background actor he received no credit for his appearances and was identified by the call sheet for the episode "The Host". He also filmed a corridor scene for the episode "Night Terrors" and was scheduled to appear in the scenes in the cave in the episode "Silicon Avatar" but was either cut or not filmed.
Young appeared as a Klingon warrior in the fifth season episode "Redemption II" for which he filmed his scenes on Tuesday 16 July 1991 and Wednesday 17 July 1991 on Paramount Stage 9 and 16. He was scheduled to appear in Ten Forward scenes in the fifth season episode "New Ground" and in sickbay scenes in the episode "The Outcast" but was not part of the final episodes.