You could say it took an act of God to bring Mariah Carey and Whitney Houston together. Next week dreamworks will release their first duet, a syrupy ballad called "When you Believe" for the animated Biblical biopic "The Prince of Egypt."

There's a lot riding on the song's success: in addition to being the first single off the Moses epic's soundtrack, it's also the first single on Carey's greatest-hits collection, "#1," and on Houston's new album, "My Love Is Your Love," both due Nov. 17.

"A lot of people are expecting this to be a heavyweight prizefight: two superstars in the ring together," says the music video's director, Phil Joanou. But through it all, he says, the divas behaved like perfect angels. Must have been the divine inspiration.