'Copa' starts something big.

Hollywood and Broadway may be a continent apart, but they share an affinity for cannibalizing their own successes.

If one sci-fi special effects epic makes a few hundred million dollars, you can count on seeing many more next summer, just as sure as one successful Broadway stage musical genre revival will inbreed others before the next Tony season.

So don't be surprised if the Jackie Gleason Theater's "Barry Manilow's Copacabane" (running through Sunday, April 15) is just the start of a new trend -- building whole musicals out of incidental characters in minor hit pop songs. If Manilow can wring a play out of Lola the showgirl and her doomed paramour Rico, how long will it be before we see:

* "John Cougar's Jack and Diane": This stage musical will follow the story of "two American kids still doin' the best that they can" 20 years after the original song. Jack is an ex-college football player whose methadone addiction kept him out of the NFL. Diane is a former jeans model working at the Dairy Queen and raising Jack's three kids. Songs include "Suckle' on Chili Dogs (Heart Attack Blues)," "Notch in the Bible Belt" and "Life Goes On (Even After the Thrill of Living is Gone)."

* "Billy Joel's Bottle of Red, Bottle of White": Based on Brenda and Eddie from Joel's "Scenes From an Italian Restaurant," this musical follows a couple that manages to survive the turmoil of the 1970s without really learning anything or becoming better at their craft. Autobiographical.