Who Will Bell the Cat?

Once, all the mice agreed that life would be better if the cat wore a bell to warn of his coming -- until a wise old mouse asked, "Who will bell the cat?"

Characters agree that an end is very desirable, until they realize someone has to carry it out. This can range from the realization that it is a Senseless Sacrifice that will fail and so not achieve the end, to The Hero refusing to harm the Reluctant Monster and demanding that Dirty Coward do it himself, at which point he melts off. It usually has to be one person who does it, with it sticking at the selection point, but that they are endangered en masse is also possible.

Contrast Just Eat Gilligan, where a simple action which would resolve the plot is not carried out because no one thinks of it. Also contrast More Hero Than Thou, Least Is First.

Comic Books

 * When the Fantastic Four testified before Congress about the Super Registration Act, Johnny said he'd like to see someone registering Doctor Doom—from a suitable distance, like a few countries away.

Film

 * In Tombstone, after Curley Bill kills the Sheriff, Wyatt Earp knocks him out and orders him taken to jail. The other cowboys surround him in order to take Bill back, until Earp puts a gun to Ike Clanton's head. Earp admits that they'll get him in a rush, but not before he blows Clanton's head off, so Clanton tells the others to back down.

Literature

 * Older Than Feudalism: Aesop's Fables contains the "Mice in Council" fable listed above.
 * In The Light Fantastic, a group of men from a mob approach Cohen the Barbarian and one of them tells him to surrender, as he says Cohen can't kill them all. Cohen replies, "Perhaps so, but you will be dead." The group suddenly decides that someone else can deal with Cohen.
 * In Rudyard Kipling's The Jungle Book, when the head wolf fails to take down the prey, the pack can take him on—but, as he reminds them, it is his right that they come one by one.
 * In Tanith Lee's The Dragon Hoard, Jasleth and other rowers hide to await the sea monster and attack it, but when it actually appears, they nervously offer each other the chance to do it.
 * In Sheri Tepper's Six Moon Dance, a Gender Swap results in the ladies suddenly deciding against a plan.

Live Action TV
"Doctor: Look at me, no plan, no backup, no weapons worth a damn. Oh, and something else I don't have: anything. To. Lose. So! If you're sitting up there in your silly little spaceships with all your silly little guns, and you've got any plans on taking the Pandorica, tonight, just remember who's standing in your way. Remember every black day I ever stopped you. And then, AND THEN, do the smart thing. Let someone else try first. *Cue shot of spaceships flying away*"
 * Invoked in a Badass Boast in the Doctor Who episode "The Pandorica Opens". The Legion of Every Species The Doctor Ever Fought is descending on the planet the Doctor's on. The Doctor gets on the radio and reminds them that he's always been able to take the respective species when they weren't working together.

"Doctor: I know you're team players and everything, but River will definitely kill at least the first three of you - River: Oh, the first seven, easy. Doctor: Seven, really? River: Eight for you, honey."
 * It comes up in "Day of the Moon" when the Doctor, River and Rory show up to rescue Amy from the Silence.

"Cercei: He just smiled and asked who proposed to keep him out."
 * This is a common trend in many seasons of Survivor, especially the later ones; many contestants might want someone in a position of power gone, but nobody wants to lead the charge against them for fear of being targeted and voted off themselves. This is doubly true if the person in power has an immunity idol, which they could easily use as insurance if they anticipate a coup.
 * Game of Thrones gives us a memory from Cercei Lannister, showing that Even Evil Has Loved Ones. While she was in labour before giving birth to her son, Joffery, Cercei's brother Jaime (widely recognized as one of the greatest swordsmen in the kingdom) was informed he could not be in the room.

Web Comics

 * Impure Blood: You go put him under arrest, then.

Western Animation

 * Merrie Melodies: "Bell Hoppy," which reverses and humorously twists and parodies this trope. Here, Sylvester (in his hapless "giant mouse chaser" persona) and his feline buddies from the Loyal Order of Alley Cats Mouse and Chowder Club attempt to bell "the largest mouse they can find" ... only here, it's the cats who hope to take advantage with their prey being belled (so they can eat him, natch), instead of the other way around (mice hoping to avoid becoming prey to a hungry cat). Naturally, Hippety Hopper – the baby kangaroo that the lisping puddy tat forever confuses for a giant mouse – happens on the scene and Sylvester tries to place the bell around his neck, but Hippety is always able to outwit Sylvester; the bell always winds up around the cat's neck and he gets clobbered. In the end, Sylvester does succeed in "belling" the mouse, and it appears that Hippety's unknown-to-him fate has been sealed ... except that the zookeeper catches the escaped kangaroo and places him in a truck to take him back to the zoo. The cats lie in wait and end up leaping into the street ... in front of the truck to get flattened!

Real Life

 * Charles Blondin, after tightrope-walking across Niagara Falls, reputedly turned to the gathered crowd and asked then "Who thinks I could do that with a person on my back?" The crowd unanimously cheered at this idea, until he pointed to some poor fellow in the front row and said, "You sir! Hop on!"