He wrote the songs: prolific gay composer Billy Strayhorn--who penned music for Nat King Cole and Duke Ellington--finally gets his due in a new documentary and CD.

The new documentary Billy Strayhorn: Lush Life tells the story of a great love between two men. But it isn't a romance, and only the titular protagonist is gay.

Billy Strayhorn wrote or cowrote several of the 20th century's greatest jazz and pop songs: "Satin Doll," "Lotus Blossom," "Something to Live For." He penned his masterpiece, "Lush Life," recorded by everyone from Nat King Cole to Rickie Lee Jones, at the age of 16.

These gems have become Strayhorn's legacy. But in his lifetime--which began in Dayton, Ohio, in 1915 and ended in a New York hospital 52 years later--the composer, arranger, and pianist was best known as Duke Ellington's right hand. As Lush Life illuminates, the two enjoyed a complex relationship, which at times hindered Strayhorn from becoming a star in his own right but also permitted him freedom he might otherwise never have enjoyed.

A small man with big appetites (he was rarely seen without a drink and a cigarette) and owlish glasses, Strayhorn boasted skills his employer lacked, including classical training. He imbued his work with a bittersweet, unconventional harmonic sensibility and rhythmic twists that hinted at the innovations of Debussy and Ravel. "Lush Life" is a quintessential saloon song, right up there with "One for My Baby," but it originally proved so daunting to Frank Sinatra that he stormed out of a recording session.

Ellington complemented his protege with showmanship and savvy. The bandleader's fame and popularity generated opportunities for Strayhorn to accomplish great feats even under duress. After a 1940 ASCAP ban forced all of Ellington's original tunes off the radio, Strayhorn and Duke's son, Mercer, had only the duration of a railroad journey to write all new material for the band. Strayhorn cooked up (and almost discarded) "Take the 'A' Train," which quickly became Ellington's signature song.

But until well after his death, Strayhorn often failed to receive accurate billing or credit for his contributions. His name was originally left off "Satin Doll," and it was Ellington alone who got the Grammy for the score of Otto Preminger's movie Anatomy of a Murder, even though Duke spent most of the filming in his hotel while Strayhorn haunted the set and composed underscore.

Because he remained hidden in plain sight, Strayhorn could conduct his personal life, including sharing a brownstone with his partner for many years, under less scrutiny. Not that this completely shielded him from discrimination in the hurly-burly, heterosexual world of jazz. He often had to write out individual charts of his pieces for every band member, as Ellington's official copyist refused to do so for him. Likewise, the bandleader's homophobic publicist made sure Duke got the lion's share of the credit--and press--for their later collaborations.

Lush Life also follows Strayhorn's adventures outside of his boss's immediate orbit: traveling to Paris to write music for an ill-fated Orson Welles stage production of Faust starring Eartha Kitt (who makes a brief cameo here); becoming involved in civil rights with his platonic love and secondary muse, Lena Horne; cooking beans and ham hocks in beer at house parties.

Yet inevitably, Ellington and Strayhorn are always drawn back together. Why? Perhaps because the latter was driven to create music of innovation and beauty, and working for a famous colleague who appreciated his gifts afforded him the fastest avenue. Had he been born white or worked in a different idiom or another era, Strayborn might have enjoyed more status and recognition. Or maybe not. As it was, as biographer David Hajdu observes, the public probably would have resisted the notion of an African-American musical genius on par with Mahler or Stravinsky--let alone a gay one.

Lush Life raises many questions, many more than its talking heads can answer. Whatever it was that drove Strayhorn, his medium was music. Alas, on the screen, the performances created specifically for this project--shot in a brightly lit, anonymous loft--feel a bit like classroom exercises. But on the Blue Note Records companion soundtrack CD, featuring 15 new recordings by pianist Hank Jones, singer Dianne Reeves, and others, the elegance and sophistication shine through. Of particular note is "My Flame Burns Blue," a gripping new interpretation of Strayhorn's final composition, "Blood Count," courtesy of Elvis Costello.

To label Strayhorn unsung is a misnomer. Forty years after his death, his repertoire sounds as rich and emotional as ever. But Billy Strayhorn: Lush Life does what its subject opted not to in his lifetime. It reveals more about the man behind the music and, more important, just how much music he was truly behind.

Billy Strayhorn: Lush Life debuts Tuesday, February 6, at 10 P.M. as part of the PBS series Independent Lens (check local listings).