West presented Operation Retrieve, the plan to infiltrate Klingon space and rescue James Kirk and Leonard McCoy, to the Federation President after the two Starfleet officers were convicted of the assassination of Klingon Chancellor Gorkon. The president overruled the plan, however, choosing to respect interstellar law in the matter.
Later, at the Khitomer Conference being held near the Romulan border, West disguised himself as a Klingon and attempted to assassinate the Federation President. Taking position behind a large window and taking aim at the president with a sniper rifle, West prepared to fire, but missed at the last instant as Captain Kirk pushed the president out of the way. After Captain Spock announced that another conspirator, Lieutenant Valeris, was in custody, West took aim at Valeris, intending to eliminate her to prevent her from testifying, but was stopped when Scotty burst through the door, shooting him with a phaser. West was thrown through the glass and fell to the ground, dying on impact. Examining the body, Colonel Worf noticed that West's blood was not Klingon, and unmasked him, revealing West's role in the conspiracy. (Star Trek VI: The Undiscovered Country)
West never actually appeared in the theatrical version of Star Trek VI since his scenes were deleted. However, he can be seen on the VHS and DVD releases of the movie, but is not listed in the cast credits at the end of VHS or DVD.
In 2009, a new cut of the DVD was released omitting the West scenes as it was offered as the first DVD cut of the theatrical release. Furthermore, the West scenes are not included on any Blu-Ray release.