When Kermit the Frog and the Muppets learn that their beloved theater is slated for demolition, a sympathetic human, Gary, and his felt-faced brother, Walter, swoop in to help the gang put on a telethon show and raise the $10 million they need to save the day.

After the success of their telethon and renewed fame, the Muppets go on a world tour and find themselves wrapped into an European jewel-heist caper headed by a Kermit the Frog look-alike and his dastardly sidekick.