Celebrity cameos are nothing new to the Muppets, but in "Muppets Most Wanted" there are so many, and some are so brief, it's almost impossible to spot them all. (The Wire has a guide to some of the more obscure ones.) With guest appearances, often no more than a single shot, by Tony Bennett, Tom Hiddleston, Celine Dion, Salma Hayek, Lady Gaga, Sean Combs and Stanley Tucci, among an almost literal cast of thousands, it's less a matter of blink-and-you'll-miss-'em than don't even try.
Some of the cameos verge on bonafide roles, especially Jemaine Clement, Ray Liotta and Danny Trejo as a trio of inmates who bond with the imprisoned Kermit in a Siberian gulag. Others are almost flagrantly pointless: James McAvoy doesn't even rate a closeup in a whirlwind appearance as a UPS guy.
Critical reaction to the parade of celeb stop-overs has been varied. Joe Williams of the St. Louis Post Dispatch says they're "dispensed without wit, as if they were interfering with the lame caper," and in his Variety review, Justin Chang says that compared to the cameo-stuffed closing of "Anchorman 2," "Muppets Most Wanted's" guest spots are "deployed to rather less hilarious or purposeful effect."
The Fresno Bee's Rick Bentley suggests that the actors' fleeting appearances are meant to keep adults engaged while their kids watch the film, but adds: "You know a movie has problems when it takes a celebrity version of 'Where's Waldo' to keep the audience entertained." The Globe and Mail's Liam Lacey says the surfeit of underwritten parts reflects "a movie which makes up in sheer volume what it lacks in inspiration." Slate's Dana Stevens remarks, "For the most part, the walk-on guests aren’t afforded even a brief opportunity to interact with their cloth co-stars, making the parade of cameos feel like an empty game of spot-the-celebrity."
But Keith Phipps at the Dissolve and Bilge Eibiri at Vulture take a different view, Phipps points out that "Muppets Most Wanted" "doesn’t move from one story point to the next, so much as it acts like a revue, switching from location to location and cameo-rich musical number to cameo-rich musical number," while Ebiri quotes a line from "Wag the Dog" "It's a pageant."
The running gag of the old "Muppet Show" was that the Muppets were a vaudeville troupe in an era that had left vaudeville behind. They did many things, but not many of them well. As the harried leader, Kermit was always near the end of his fraying rope, each evening's show always perched on the edge of disaster. The Muppets' weekly guests, who grew more famous as the show's popularity waxed, were plopped down amid the carefully staged chaos, to delightfully ill-fitting effect:
Chances are almost no one who sees "Muppets Most Wanted" will notice Toby Jones and Mackenzie Crook as a pair of museum guards or Miranda Richardson as a German hausfrau, but that's entirely on purpose. They're not meant to fit in, any more than Saoirse Ronan does as a ballerina paired with two gangly, enormous Muppet dancing partners. Even the movie has trouble keeping track of who they're meant to be playing: Usher is cast as (wait for it) an usher, and as the gulag convicts bid each other goodnight, an offscreen voice calls out, "Good night, Danny Trejo."
That goes equally for the absurd number of in-joke film references director James Bobin crams into nearly every scene: Busby Berkeley numbers, "Oldboy" and "Raising Arizona" in the first few minutes alone. Unlike, say, the manatee-run joke combine of "Family Guy," "Muppets Most Wanted" doesn't make the references the point: Missing them doesn't hurt the film in the least, and even if you pick up on them, they're gone in an instant. That they're pointless is kind of the point.