As The Muppets tour the world, a villainous lookalike to Kermit the Frog switches places with him and begins committing crimes. Walter is the earnest number one fan of the Muppets, and this movie starts at the very end of the last film, with Walter officially joining the Muppets for good. Trying to determine what they should do next, they are approached by a British manager, Dominic Badguy, who suggests they tour all over Europe. Kermit the Frog, the leader of the Muppets, is skeptical, but Walter thinks it would be a good idea for the Muppets' exposure to new people. They accept Badguy's proposal, not realizing he is in fact a bad guy, the assistant of the evil Constantine, the world's most dangerous frog. Constantine looks exactly like Kermit the Frog, except that he has a mole on his face. Constantine escapes from the Russian Gulag in which he is being held, and heads off to meet Badguy and the Muppets. In Berlin, their first stop, Kermit is frustrated that everyone is listening to Badguy's suggestions instead of his own, so he heads out on a walk. While on the walk, Constantine jumps out, glues a mole to Kermit's face, and paints over his own. When the police arrive, they arrest Kermit, mistakenly thinking he is Constantine, and take him to the Russian Gulag, while Constantine returns, doing an impression of Kermit that convinces most of the Muppets... except for Walter. As they go around the world, Constantine and Badguy break into a variety of museums to retrieve the artifacts they will need for their final destination: London, to steal the crown jewels. Although Interpol and the CIA are hot on the trail, Walter is the first to stumble upon the wicked truth. Walter, along with the comedian Fozzie the Bear and the Muppet resident drummer Animal, escape from the Muppet troupe to break Kermit out of the Gulag, as he's the only one who can stop Constantine once and for all.
Best part of story, including ending:
This is a terrific Muppet film, one of the best in years. Absolutely hilarious, with catchy and witty songs, and more celebrity cameos than any film in recent memory.
Best scene in story:
Constantine's seduction of Miss Piggy, Kermit's love interest, includes singing a sultry disco tune to her. It's an amazing song and a hilarious sequence.
Opinion about the main character:
Walter is the surrogate for the audience, the average joe who can step outside the madness and comment on it. Plus, he loves the Muppets as much as we do.