'As long as there are Muppets," muses a little felt guy named Walter, "there is still hope."

And indeed, there is something hopeful about The Muppets - Disney's rollicking reboot of the late Jim Henson's furball franchise. The seventh Muppet movie, and the first since 1999's intergalactic dud, Muppets From Space, this one sprang from Forgetting Sarah Marshall star Jason Segel's deep and abiding affection for Kermit, Rowlf, Gonzo, et al. He and Sarah Marshall's writer/director Nicholas Stoller were determined to return the Muppets to their glory - to goofball song-and-dance numbers, to slapstick silliness, to winking we-know-this-is-a-movie cutup commentary. To all of that, but with heart.

And mission accomplished. Stoller and Segel scripted; James Bobin, veteran of the nutty, deadpan series Flight of the Conchords, directed; and the Conchords' Bret McKenzie wrote the new tunes.

Beginning with a dopily upbeat but still impossibly charming sing-along called "Life's a Happy Song" (it starts as a simple duet and ends with all of Smalltown, USA, kicking up their heels), The Muppets treats its titular heroes with affection and respect, even as Fozzie Bear shows off his "fart shoes" and toilet humor abounds.

The aforementioned Walter (voiced by Peter Linz) is the diminutive sibling to Segel's Gary. The possibly peculiar fact that one is a tiny puppet and the other a lumbering human, is never addressed - they're brothers, so there. And when Gary and his girlfriend Mary (Amy Adams) plan a trip to Los Angeles to celebrate their anniversary, they take Walter along. The legendary Muppet Studio is there, and Walter can't wait.

But the Muppets' glory days are long gone, the studio is a ghostly shambles, and Walter, by dint of having hidden under a table in Kermit's office, overhears a greedy oil baron's scheme to level the Muppet Theater and surrounding studio and drill for crude. Chris Cooper, keeping a straight face and even diving into a rap number, is the arch-villain, Tex Richman.

And so Walter (and Gary and Mary) hunt down Kermit, tell him of the sinister plan, and then head hither and yon to collect the disbanded Muppets and organize a reunion and a telethon to raise the $10 million needed to save the studio. Cameos by Jack Black, Zach Galifianakis, Sarah Silverman, Rashida Jones, and Emily Blunt ensue.

And Neil Patrick Harris, Selena Gomez, Mickey Rooney, David Grohl, Judd Hirsch, John Krasinski, and James Carville show up as themselves.

Segel manages to seem completely in the reality of the moment while also standing outside of it, chortling appreciatively, while Adams plays wide-eyed and perky - but can still look mighty perturbed. Gary doesn't get it that she wants intimate time with her beau. Oblivious, he lets Walter tag along wherever they go, obsessing about Kermie and company.

And Kermie and company are in top form. Miss Piggy has moved on - she's an Anna Wintour-like fashion mag diva, working out of Paris - and it takes all of the affable amphibian's persuasive powers to get her to agree to come back to L.A. and help the gang. But she does, and the telethon goes on, and . . . well, is the Muppet Studio saved from the wrecking ball?

Is a frog green?