In that show, Mr. Scott expressed astonishment at the approach of that ship's engineer, Geordie LaForge, to telling his captain how long it would take to work through a particular problem. "Oh, you didn't tell him how long it would really take, did you?" When Mr. LaForge said he had, Mr. Scott replied with exasperation, "Oh, laddie, you've got a lot to learn if you want people to think of you as a miracle worker!"

James Montgomery Doohan was born in Vancouver, British Columbia, on March 3, 1920. He was the youngest of four children, and his father, Mr. Doohan would later write in his memoir, "Beam Me Up, Scotty," was an abusive alcoholic. Mr. Doohan served in World War II, and was struck by six bullets during the D-Day Invasion in Normandy. One of the bullets blew off his middle right finger, an injury he would later conceal from the Star Trek television cameras.

Married three times, he is survived by his third wife, the former Wende Braunberger, and seven children. The four children from his first marriage, now grown, are Larkin, Deirdre, Montgomery and Christopher; his third marriage produced three children: Eric, Thomas and Sarah, who was born in 2000 when Mr. Doohan was 80.

When he first auditioned for the role of ship's engineer with Gene Roddenberry, the creator of Star Trek, Mr. Doohan read the lines with a variety of accents, including French and German. "They both decided an engineer has got to be a Scotsman," Mr. Stevens recalled.

Mr. Doohan became so closely associated with his character that it was difficult for him to get other parts. But if he resented having taken a role that all but ended his acting career, he did not show it, said Walter Koenig, who played Ensign Pavel Chekov in the original television series and rode the lucrative convention circuit with him.