The only film in which Mickey Mouse is shown in uniform, he is seen in a photo on the wall as a soldier.
"Out of the Frying Pan Into the Firing Line" from 1942 is the fourth and last time Thelma Boardman voiced Minnie Mouse. She has voiced Minnie since 1937 in the radio show "The Mickey Mouse Theater of the Air", and voiced her in Mickey Mouse Cartoons starting with "The Little Whirlwind (1941)" from 1941, followed by 1941s "The Nifty Nineties (1941)" and the prior 1942 Mickey Mouse Cartoon "Mickey's Birthday Party (1942)". Ruth Clifford took over as the next voice for Minnie starting with the 1944 Pluto Cartoon "First Aiders (1944)". "Out of the Frying Pan Into the Firing Line" also was the second to last time Thelma Boardman voiced a character in a Disney film. The final film she did voice work for was in the 1942 feature length animated film "Bambi (1942)", where she voiced multiple characters (the Girl Bunny, the Quail Mother and the Female Pheasant).
The image of waste grease being poured into a vast whirlpool in "Out of the Frying Pan into the Firing Line" from 1942 is adapted from another whirlpool, animated for the climactic scenes of "The Sorcerer's Apprentice" from 1940s "Fantasia (1940)", in which Mickey gets twisted in.
1942s "Out of the Frying Pan into the Firing Line"'s main titles were underscored by an instrumental version of "Yankee Doodle Spirit", a song written for another Disney public-service Cartoon, the 1942 Donald Duck documentary Cartoon "The New Spirit (1942)".
Studio cutting records of "Out of the Frying Pan into the Firing Line" from 1942 indicate that both Jeanette Tonner and Thelma Boardman (who voiced Minnie in Cartoons since the 1941 Mickey Mouse Cartoon "The Little Whirlwind (1941)", and has voiced her even earlier since 1937 starting with the radio show "The Mickey Mouse Theater of the Air"), separately, recorded lines of dialogue for Minnie Mouse.