BIO
His first starring television role was in 1981 in the cautionary NBC movie Angel Dusted. Also in 1981, he co-starred in the made-for-TV movie Midnight Offerings as the love interest of two dueling teenage classmates who happen to be witches, played by Melissa Sue Anderson and Mary Elizabeth McDonough. In 1983, he starred in Bay City Blues as a baseball player in the minor leagues. The show was canceled after just four episodes. In 1984, Cassidy portrayed the initial love interest to Heather Langenkamp's character in the film Nickel Mountain.
In 1986, Cassidy played a cadet at a military academy in Dress Gray and appeared in the holiday TV movie Christmas Eve with Loretta Young. He had a role as a gambling soldier in the Ryan O'Neal sports and Las Vegas gambling film Fever Pitch. In 1988, he starred in the CBS television series Dirty Dancing, based on the film. In 1989, he appeared in Longtime Companion, portraying an actor who eventually contracts AIDS. In 1994, he appeared in the films I'll Do Anything and How the West Was Fun with Mary-Kate and Ashley Olsen. In 1997, he had a recurring role on TV's Lois & Clark: The New Adventures of Superman as Leslie Luckaby and had another Superman-related recurring role as the biological father of Lana Lang in Smallville, which was televised from 2001 to 2011.
He co-starred alongside his half-brother David in a 2009 ABC Family comedy series entitled Ruby & The Rockits created by his brother Shaun. ABC Family announced on September 12, 2009, that the show had been canceled.
Cassidy played Frederic in the 1981 national tour of Gilbert and Sullivan's The Pirates of Penzance before taking over the role on Broadway in 1982. Cassidy's next Broadway role was Jeff Barry in the Ellie Greenwich jukebox musical Leader of the Pack, which opened in April 1985. He originated the role of The Balladeer in the original Off-Broadway production of Stephen Sondheim's Assassins at Playwrights Horizons, which opened in December 1990 in previews.
Cassidy starred at the Elitch Theatre in The Robber Bridegroom in 1991. This was the 100-year Anniversary of the theatre and it was the final production at the theatre before it was dormant for over 20-years.
In 1993, Cassidy starred as Bobby opposite Carol Burnett in a Los Angeles production of Sondheim's musical Company. In 1995, he portrayed John Wilkes Booth in the Los Angeles Repertory staging of Assassins.
In 1998, he played Macheath in a Los Angeles Reprise! production of The Threepenny Opera; he was nominated for the Garland Award for Best Actor for his work in the role. In 1999, he played the title character in a national tour of Joseph and the Amazing Technicolor Dreamcoat.
In 2000, Cassidy co-starred with Cheryl Ladd in Annie Get Your Gun on Broadway as Frank Butler (replacement). He later reprised his role of Frank Butler alongside Patti LuPone and George Hearn in August 2010 concert presentations at the Ravinia Festival in Illinois, directed by Lonny Price.
In 2001 he played Radames in the national tour of the musical Aida; he won the 2002 National Broadway Theatre Award for Best Actor in a Touring Musical before playing the role on Broadway in June 2002.
In 2004-05 he was back on Broadway in 42nd Street as Julian Marsh (replacement) playing opposite his mother as Dorothy Brock. He appeared in a US national tour of Joseph and the Amazing Technicolor Dreamcoat, once again playing the title role, starting in September 2005.