Flush with their revival's success, Kermit the Frog and his friends are approached by Dominic Badguy (Ricky Gervais) to go on a world tour. Unbeknownst to them, this is all part of the sinister plan of Constantine, the world's most evil frog, to become the greatest thief of all time. After making sure that Kermit is jailed as him, Constantine impersonates him to use the Muppets' tour as cover for his scheme. While Sam the Eagle and Inspector Jean Pierre Napoleon (Ty Burrell) investigate, the Muppets think their boss seems strangely changed even as Kermit desperately attempts to escape to stop the impostor. Only when Walter, Fozzie, and Animal realize the truth, is there a chance to stop Constantine from pulling off the crime of the century.