Stardate 41601.3: The Enterprise rushes to rescue a shuttlecraft carrying Troi, and the Away Team discovers that Armus, an evil entity, is preventing them from saving Troi and the shuttle pilot. To make sure that its point is clear, Armus kills Tasha Yar and torments Troi and the rest of the crew.
teleplay by Joseph Stefano and Hannah Louise Shearer
story by Joseph Stefano
directed by Joseph L. Scanlan
music by Ron Jones
Guest Cast: Mart McChesney (Armus), Ron Gans (voice of Armus), Walker Boone (Leyland T. Lynch), Brad Zerbst (Nurse), Raymond Forchion (Ben Prieto)
Notes: Denise Crosby officially leaves the regular cast with this episode – though she would appear later in the series, but not always as Tasha.
LogBook entry by Earl Green