OutKast's Andre 3000 appears on Esthero's Wikked Lil' Girls album, due this spring. The Grammy-winning hip-hop star agreed to sing on the Toronto-based singer's record -- a sexy, sophisticated blend of jazz, pop and R&B -- after she sent him four songs this summer.

"He called me a couple of days later," Esthero says, "and said, 'What are we doing, and when?'"

Esthero flew down to OutKast's Stankonia Studios in Atlanta in July, where Andre contributed vocals to "Jungle Book," which Esthero describes as "a fantasy song about being tired of your surroundings and moving to the jungle and living in a tree fort and dancing with fireflies."

After the two hung out in the lounge, Andre emerged with his animalistic, cannibalistic vocal part, featuring the line "I'll eat you alive."

"When I heard it, I thought he said, 'I'll eat you all night,' and I was laughing," Esthero says. "I said to him, 'I don't think you can say that,' and he said, 'Noooooo, I'm saying, 'I'll eat you alive -- like a cannibal.' . . . He's so talented, so humble and so fun. I'll remember the night in the studio with him forever."

Wikked -- which will follow Esthero's just-released We R in Need of a Musical Revolution! EP -- also features Cee-Lo on the plaintive, gospel-like "Gone" and Sean Lennon on the blissful "Every Day Is a Holiday (With You)."

"Working with Esthero is like mainlining inspiration," says the effusive Lennon, who co-wrote the track. "If songwriting is a highway, Esthero is a souped-up pink Lamborghini. If you don't wear a seatbelt, you get musical whiplash. 'Every Day' was a garden already in bloom -- she simply wanted someone to walk through it with. Lucky me."