Mariah Carey is making a special cameo to highlight a legendary singer…

The first trailer has been released for Luther: Never Too Much, a documentary that features an appearance by the 54-year-old half-Venezuelan Grammy-winning singer, ahead of the film’s world premiere on Sunday at the Sundance Film Festival.

Dawn Porter directs the film about the late Luther Vandross, widely considered one of the greatest vocalists in recording industry history but whose talents as a songwriter have gone under-recognized.

As the film explores, early in his career Vandross became a much sought after background singer – performing with Barbra Streisand, RobertaFlack, Bette Midler and other big names – and became a major success of a singer of television jingles (for Juicy Fruit gum, Miller beer, among other products).

He carefully crafted his own solo career, building it around hits he wrote himself including “Power of Love,” “Any Love,” and “Never Too Much.”

“Luther: Never Too Much… chronicles the story of a vocal virtuoso,” notes a description of the film, which debuts in the Premieres section of Sundance. “Using a wealth of rarely seen archives, Luther tells his own story with assistance from his closest friends and musical collaborators including Carey, who performed “Endless Love” with him, Dionne Warwick, Valerie Simpson and Flack. The film relives the many stunning moments of Luther’s musical career, while exploring his unrequited love life, health struggles, and a lifelong battle to earn the respect his music deserved.”

Luther: Never Too Much is an acquisition title at Sundance, with Sony Music Entertainment handling sales. A section of the film is devoted to Vandross’s collaboration with David Bowie on the latter’s 1975 album Young Americans. Vandross began by doing background vocals on the project, but his role expanded as Bowie recognized the breadth of his gifts.

“Luther arranges the entire album with David Bowie — as a 20-something year old kid,” Porter told Deadline in an interview at Sundance. “And then he takes Luther on tour with him. And so when you see the generosity of an artist like David Bowie, and you think about that kind of combination of sounds, that is what music and art is all about. These artists, they’re responding to what inspires them. And I feel like that’s kind of something we could all think about. We’re thinking a lot about our differences and these artists, they’re showing us how we’re the same.”

Click here to see the official trailer on Deadline.com.