After their successful return, the Muppets decide to embark on a world tour, managed by the sinister Dominic Badguy. Unbeknownst to them, Dominic is the second-in-command to Constantine, the world's most dangerous frog, who escapes from a Russian gulag. To facilitate his next heist, Constantine swaps identities with Kermit. The unknowing Muppets continue their tour, unaware that Kermit has been mistakenly imprisoned in the gulag while Constantine uses the chaos to plan a series of elaborate robberies across the tour’s locations.

As Constantine poses as Kermit, his unusual behavior raises suspicions among the Muppets, though they believe his odd actions are simply due to tour stress. Meanwhile, Kermit struggles to escape and prove his innocence as he forms unlikely alliances within the gulag. An Interpol detective and a CIA agent start investigating the high-profile heists linked to the tour, leading to crisscrossed paths and comedic mishaps. As events escalate, the Muppets must confront their doubts and work together to unveil the truth behind the deception before it's too late.