Sam tells his imaginary friend T-Rex to get lost, but it's Sam who vanishes -- into a box of crayons.
This realm between fantasy and reality is the setting for "Imagine," a funny, fanciful musical by playwright and children's book author Doug Cooney and Los Angeles composer David O at South Coast Repertory through Sunday.
The show is the company's latest commission for its Theatre for Young Audiences series, which could use more shows like this quirky romp, directed with clarity by Stefan Novinski, with deft performances by a cast of twentysomething professionals.
Visual pop is provided by costume designer Angela Balogh Calin, who has fun with a colorful palette and the offbeat characters, and by set designer Donna Marquet, whose contributions include a playground and a clever, oversized crayon box complete with sharpener, curly shavings and goggle-eyed puppet faces.
Cooney previously collaborated with O on a youth musical, "The Legend of Alex," produced by the Mark Taper Forum's P.L.A.Y. company. He has lighter fun here.
Mixing affirming messages and madcap humor, he mines the possibilities of an imaginary friends' code of conduct and shows how a little creative thinking can help shy kids and loners find their niche.
O, whose latest work, "A Map of Los Angeles," was commissioned by the Los Angeles Master Chorale, adds considerable substance and bounce to "Imagine" with an inventive score featuring a madrigal composed of varied sounds of laughter and a boisterous "Princess Song."
The latter complements Cooney's spoof lyrics as imaginary duo Tullabelle (Meaghan Boeing) and Lullabelle (Diana Burbano) rope Sam into their favorite game: playing dress-up in the frilliest pink princess dresses ever.
When Sam (James Michael Lambert) disappears, it's T-Rex (Brett Ryback) to the rescue. Little Debbie (Jamey Hood), the world's oldest imaginary friend (because the school principal still believes), tells T-Rex that the only way to help Sam is to befriend a real kid with no imagination.
Serious-minded Rachel (Dawn-Lyen Gardner) fits the bill. Once she discovers the fun of dreaming up adventures, she and T-Rex take off for Africa, the South Pole and a Swiss cheese moon populated by green aliens, a route T-Rex hopes will lead to Sam.
Meanwhile, Sam finds a friend in a quip-happy crayon named Shadow (Hood again, a comic standout), who'd like a real kid of her own. In the satisfying conclusion, T-Rex discovers how imaginary friends move on, and Sam and Rachel see what friendship means in the real world.
Where: South Coast Repertory, 655 Town Center Drive, Costa Mesa
When: 7 p.m. Friday; 2, 4:30 and 7:30 p.m. Saturday; 2 and 4:30 p.m. Sunday
Price: $15 to $27
Contact: (714) 708-5555
Running time: 1 hour, 10 minutes