Cheese Chasers is a 1951 Merrie Melodies cartoon directed by Chuck Jones, and starring Hubie and Bertie in their final appearances of the Classic era. Also starring are Claude Cat and a bulldog predecessor to Marc Anthony. Mel Blanc plays Claude and Hubie, while Stan Freberg plays Bertie.
At the end of a raid on a cheese factory, Hubie steps out of a wheel of cheese and nauseated. Bertie stumbles out after. Hubie determines that, based on the amount of cheese the average mouse eats in their lifetime (12 lbs.), they've eaten enough to have lived two thousand years. Determining that they can no longer stomach cheese, and with nothing else to live for, they determine their only course of action: suicide. They return home, where they write a generic suicide note ("Goodbye, cruel world!"), and introduce themselves to the gullet of a sleeping Claude Cat.
Claude immediately wakes up and spits the mice out. Believing that "something's rotten in Denmark", he figures the mice are poisoned, and refuses to eat them. After several attempts to refuse to eat them, and attempting in vain to convince himself it's all a bad dream, he determines he can no longer eat mice, and also decides to commit suicide. Leaving an equally generic suicide note ("P.S., no P.S."), Claude heads outside and punches Marc Anthony.
Marc Anthony sees Claude standing there with a blindfold and a cigarette, and asks what's going on. When Claude begs the bulldog to "massacre" him, Marc Anthony thinks "something's decidedly fishy here". It gets worse when Hubie and Bertie run out, trying to get Claude to eat them. Marc Anthony figures out that Claude no longer wants to eat mice, and the mice now hate cheese, but after using an adding machine to figure it out, concludes, "It just don't add up!" He runs after a dog catcher wanting to get committed ("Hey, wait for me! Wait for baby!"), with Claude ("Hey, wait for me! You gotta massacre me!") and the mice ("Wait, you cowardly cat!") in hot pursuit, still bent on ending their own lives.
Hubie: "Hey, Boit."
Bertie: "Yeah-yeah, Hubie. What is it, huh? What is it?"
Hubie: "Let's quit."
Bertie: "Yeah-yeah, sure-sure. I don't feel so good."
Hubie: "Boit, an average mouse eats 12 pounds of cheese in its lifetime. I figure tonight we've lived 2,000 years."
Bertie: "Hubie, I'll never be able to touch the stuff again."
Hubie: "Me neither. So there's nothing left to live for."
Bertie: "You mean?!" :Hubie: [nods solemnly] "Come on, Boit, let's get it over with."
Bertie: "Yeah yeah. Over." *hic* ----
Marc Anthony: "You're a cat, right?"
Marc Anthony: "And cats eat mice, right?"
Claude: [shaking head] "NO!!"
Marc Anthony: [looking confused] "And you two... you're mice, right?" [Hubie and Bertie nod]
Marc Anthony: "And mice, they eat cheese, right?"
Hubie and Bertie: "Cheese?! YAAAAAAAHHH! Don't mention that word!" [Marc Anthony looks confused again. SFX: bay-woop!]
Marc Anthony: [the dog is at an adding machine] "Let's see now. Mice don't like cheese... [types on machine, pulls lever] ...and mice want cat to eat them. [types on machine, pulls lever again] Now then, cat don't wanna eat mice... [types on machine, pulls lever again] ...but cat wants dog to massacre him. [types on machine, pulls lever again, and looks at results] It just don't add up! [Dog then hears a dog pound driving by and runs to it, and runs away from Claude, Hubie and Bertie] Hey, wait for me! Wait for baby!"
Claude: [while running up to runaway Dog] "Hey, wait for me! You gotta massacre me!"
Hubie and Bertie: [while running up to Claude Cat and the Dog] "Wait, you cowardly cat!" [the closing credits start]