Life Is a Circus, Charlie Brown

Polly:
Hugo! Fifi! Come back! Hugo the Great! Fifi! Come back!

Charlie Brown:
[watching as the circus train pulls away with Snoopy] Good grief. He's gone. Dognapped.

Charlie Brown:
His career is being my dog!

Charlie Brown:
[to Lucy, who has taken it upon herself to board up Snoopy's doghouse] What are you doing?

Lucy van Pelt:
Since Snoopy 'obviously' isn't coming back, we're closing down his house.

Charlie Brown:
[as she walks away] What do you mean he's not coming back?