Hogan's Heroes, for all that it's a comedy, still has moments of acknowledging that they're in the middle of a war. In one notable episode, Hogan attempts to seduce a female SS officer for information. She then confesses that she has no way out of her job without dying and is probably going to get shot soon anyway, ending with a pitiable "Help me...". Then it turns out she's going to the exact place where Hogan knows Allied forces are going to bomb and he can't tell her a word of it even to save her life. She eventually doesn't go, but still.. the look on their faces.
Downplayed a little when it turns out she was testing Hogan. Newkirk winds up in a very similar situation in "Is there a Traitor in the House?" and reacts the same way.
Another is when General Burkhalter steals a painting from the Louvre and brings it smugly to Stalag 13. LeBeau, enraged at this further pillaging of his country, sneaks into Klink's office and steals the painting. When he removes it from its frame and holds it up in front of him, the surge of sorrow and anger causes him to start crying.
LeBeau being shot in the cold opening of "That's No Lady, That's My Spy." Newkirk turns deadly serious and says, softly, "Colonel, my little mate's been hit." Luckily, the bullet only grazed him. LeBeau just fainted from seeing blood.
In "The Sergeant's Analyst", Schultz is caught napping in the barracks and is ordered to the Russian front by Burkhalter. Klink first tries to defend him but then chickens out and starts calling Schultz a stupid useless guard. Its very hard not to feel for Schultz who's trying not to cry in that scene.
"The Great Impersonation" has the heartbreak and worry on Hogan and Kinch's faces when Kinch comes up the tunnel without Carter, LeBeau, and Newkirk.
"D-Day at Stalag 13" has one in the form of General Von Scheider and his wife Lilli, who happens to be an Allied spy that had been abandoned by her bosses after her marriage. Hogan has orders to secure her escape to London. Though she hides it well, Lilli makes it clear that she is not really okay with leaving her husband, despite everything. Meanwhile the General is absolutely heartbroken when he realizes that she is gone.