LOS ANGELES — Here's a quiz for cartoon lovers: What do you get when you combine the acerbic pop-culture references of "The Simpsons" with "Family Guy's" irony and the broad slapstick humor of "SpongeBob SquarePants"?

For veteran animators Dan Povenmire and Jeff "Swampy" Marsh, the result is Phineas and Ferb," a world populated by a pet platypus and a kid with a triangular head who has a penchant for turning his backyard into things like ski resorts, surfing beaches and monster-truck rallies without his parents ever catching on.

"We always like to say 'Phineas and Ferb' is about the midway point between 'Family Guy' and 'SpongeBob,' " said Povenmire, co-creator with Marsh of the 15-minute show that airs every night this month at 8 on the Disney Channel.

Povenmire said the show uses a lot of understated acting that is a "Family Guy" hallmark, "but we still have big cartoony stuff happening."

The most cartoony would be Phineas' triangular head — were it not for his pet, a platypus named Perry.

"The platypus is sorely underused in animation," quipped Marsh, who otherwise can't really explain the selection of a semi-aquatic, egg-laying mammal to play the sitcom role of the family dog.

Perry, however, is no ordinary platypus, even by cartoon standards. Unbeknownst to his family, he (or she) is also a secret government agent code-named P who regularly dons a hat and trench coat to save the world from the mad scientist Dr. Doofenschmirtz. This, while Phineas and his half brother, Ferb, are creating elaborate contraptions and events in their backyard.

The show skips back and forth between kid themes (Phineas and Ferb attempting to carve their sister's face into Mount Rushmore, for example) to references only older people might get. The latter include the battles between Agent P and Doofenschmirtz —high comedy that bears a striking resemblance to that found in "Man From U.N.C.L.E" reruns.

Such a slapstick dichotomy, said the show's 15-year-old star, Vincent Martella (the voice of Phineas), should have families watching together.

"You don't want a show that just the kids are going to be watching 24/7 and annoy the heck out of the parents. You want the parents to say, 'I like watching this too,' " Martella said in the community room of his family's Hollywood Hills apartment complex.

It also has a motivational message for viewers, said Alyson Stoner, the 14-year-old actress who voices Phineas' puppy-love interest.

There is the reminder that kids shouldn't be afraid to go outside and create their own backyard adventures.

"It's kind of teaching kids that if you are dedicated and are motivated you can really do a lot with your life."