 In the third season finale "Abyssinia, Henry", Henry Blake is sent  home, to coincide with McLean Stevenson (qv)s departure from the  show. In a surprise twist at the end of the episode, the characters  learn that Blakes plane was shot down en route to Japan, and  everyone aboard died. This was kept a surprise from the cast (with  one exception, Alan Alda (qv)) until the moment when  Gary Burghoff (qv)s character ran into the operating room to  announce the news. The producers intent was to capture the casts  genuine shock and surprise, and to remind the audience that war  takes friend and foe alike. A technical mistake required a second  take to be filmed, and in that take one of the cast dropped a  surgical instrument on the floor, banging loudly as it hit. This  mistake was left in, since it so well fit the scene. McLean  Stevenson was on the set as the scene was shot, and left almost  immediately afterward. A catered wrap party had been prepared, but  after filming was finished, nobody felt like celebrating, and they  simply went home.