Born in Cambridge, Ohio, Eyen is best known for works at opposite ends of the theatrical spectrum. Mainstream theatergoers became acquainted with him in 1981 when he partnered with composer Henry Krieger and director Michael Bennett to write the book and lyrics for Dreamgirls, the hit Broadway musical about an African American female singing trio. Eyen's career started, however, with avant garde plays and musicals that he wrote and directed off-off Broadway in the early 1960s, which eventually led to off-Broadway success in the 1970s with the controversial nudity-filled performance-art play The Dirtiest Show in Town and Women Behind Bars, a camp parody of women's prison exploitation films.
Other early off-off-Broadway credits include writing (and usually directing) My Next Husband Will Be A Beauty! (1964), Frustata, The Dirty Little Girl With The Paper Rose Stuck In Her Head, Is Demented! (1964), The White Whore And The Bit Player (1964), Can't You See A Prince? (1965), Court (1965), The Last Great Cocktail Party (1965), The Demented World Of Tom Eyen (1965), Why Hanna's Skirt Won't Stay Down; Or, Admission 10c (1965, the title character has been described as an icon representative of all the crudeness, exuberance, decadence and off-the-cuff profundities of the era), Give My Regards To Off-Off Broadway (1966), Grand Tenement/November 22nd (1967), Sarah B. Divine! (1967), Kama Sutra, The (An Organic Happening) (1968), Who Killed My Bald Sister Sophie? Or, Thank God For Small Favours! (1968), When Johnny Comes Dancing Home Again (1968), Alice Through A Glass Lightly (1968), 4 Noh Plays (1969), Caution: A Love Story (1969), The Dirtiest Show in Town (1970, with later versions off-Broadway and in London's West End), Areatha In The Ice Palace; Or, The Fully Guaranteed Fuck-Me Doll (1970), Gertrude Stein And Other Great Men (1970), Lana Got Laid In Lebanon (1970), What Is Making Gilda So Gray?; Or, It Just Depends On Who You Get (1970), and 2008: A Spaced Oddity (1974).
In 1973, he co-wrote the book for and directed one of Broadway's most notorious flops, the Paul Jabara disco musical Rachael Lily Rosenbloom (And Don't You Ever Forget It), which closed after seven previews. The lead character, a flamboyant entertainer, had been inspired by Midler, who nevertheless passed on the role.
Following this setback, Eyen began to commute to Los Angeles to write for television. He contributed scripts to the 1976-78 ground-breaking evening soap opera parody. Mary Hartman, Mary Hartman, produced by Norman Lear. In 1978, he earned an Emmy Award nomination for writing Midler's television special Ol' Red Hair is Back.
Eyen's campy-disturbing send-up of women's prison exploitation movies, Women Behind Bars, became a major off-Broadway hit in 1975, first with Pat Ast, and then with Divine, playing the lead role of the sadistic matron in drag. The New York Times called it "an extraordinarily interesting work from one of America's most innovative and versatile playwrights.. He followed up on this success with The Neon Woman, another off-Broadway play starring Divine in 1978.
In 1980, Eyen directed a film version of The Dirtiest Show In Town, with John Wesley Shipp baring all, for the cable network Showtime, making it the first "made for cable" television movie. The film's explicit nudity and depiction of gay characters was considered a breakthrough of sexual expression in the early days of cable television.
Produced on Broadway in 1981, Dreamgirls' was the biggest success of Eyen's career. It was nominated for thirteen Tony Awards, including two for Eyen: Best Book and, as lyricist, Best Original Score. The show won six Tonys, including Best Book. It also earned Eyen a Drama Desk Award nomination for Outstanding Lyrics. The original cast album won Eyen a Grammy Award as lyricist, and one of the show's songs, "And I Am Telling You I'm Not Going", sung by Holliday, became a top hit.
When a film adaptation of Dreamgirls by writer/director Bill Condon was released in 2006 by DreamWorks and Paramount Pictures, the soundtrack became a number one hit, and two of Eyen's songs from the soundtrack, "And I Am Telling You I'm Not Going", sung by Jennifer Hudson, and "One Night Only", sung by Beyoncé Knowles (credited as Deena Jones & The Dreams), became hits again. To promote the film's release, DreamWorks and the licensee of the musical, The Tams-Witmark Music Library, paid the licensing fees for all non-professional stage performances of Dreamgirls for 2006. As a result, more than fifty high schools, colleges, and community theaters staged productions of Dreamgirls in 2006.
Eyen's 1984 attempt to duplicate his Dreamgirls success with Kicks:The Showgirl Musical, a collaboration with composer Alan Menken about members of the Rockettes during World War II, never made it past the workshop stages, though individual numbers from the show are often performed in concert.
Eyen died of AIDS-related complications in Palm Beach, Florida at the age of 50. A memorial service was held at the St. James Theatre in New York City on September 23 1991. In 1993, he posthumously received the Jerome Lawrence & Robert E. Lee Theatre Research Institute Award at The Ohio State University, where his papers are archived.