He starred in the original production of Maltby and Shire's hit Off-Broadway musical Closer Than Ever in 1989 and the 2001 West End revival of Cole Porter's Kiss Me, Kate.

While still a student he began his professional career performing with the Pittsburgh Civic Light Opera during the 1978 and 1979 seasons, appearing in productions of Half a Sixpence, Camelot, Good News, The Red Mill, Cabaret, and Funny Girl among others.

[2] While in his final year in college, he was cast by Jerome Robbins to play Diesel in the 1980 Broadway revival of Leonard Bernstein's West Side Story.

[1] In May of that same year he joined the original Broadway cast of Grand Hotel, replacing the ailing David Carroll as Baron Felix Von Gaigern.

[10] In 1994 he appeared as Victor Duchesi in the original production of the Sherman Brothers's Busker Alley, which through unhappy circumstance never made it to Broadway, although it had been scheduled to do so.

revival of The Pajama Game[18] and he played the role of Billy Crocker in Anything Goes at UCLA's Freud Playhouse in Westwood, Los Angeles, California.

[20] That same year he returned to Broadway to portray the role of Billy Flynn again in the revival of Chicago and he sang at the New York Festival of Song at Carnegie Hall in a concert honoring Hal Prince.

In 2006 he played the title role in Andrew Lloyd Webber's The Phantom of the Opera for the new production in at The Venetian Resort in Las Vegas which was directed by Hal Prince.

[23] On June 24, 2011, five days after leaving Chicago, Barrett began starring as famous character Hannibal Lecter, in SILENCE!

The show has run for longer than its initial limited engagement at 80 St. Marks Place, directed and choreographed by Christopher Gattelli.

In June and July 2016, Barrett played Georges in a production of La Cage aux Folles at the Signature Theatre in Arlington, Virginia.