[3][4][5] Roberts attended the High School of Music & Art[6] and Northwestern University, and he made his Broadway debut in 1962 with a role in the play Something About a Soldier.

In a rare, big-screen leading role, Roberts starred in the 1983 horror movie Amityville 3-D, playing John Baxter, a deeply skeptical, Doubting Thomas-type tabloid journalist who buys the infamous and possessed haunted house.

Roberts also enjoyed screentime in the Walt Disney screwball comedy The Million Dollar Duck and the stage-to-screen adaptation of Star Spangled Girl, both 1971 (and both co-starring Sandy Duncan), Key Exchange and Le Sauvage, both 1985, 1986's Seize the Day, and 2005's Twelve and Holding, among others.

Roberts and Lauren Tewes' character, cruise ship director Julie McCoy, both fall in love with each other, but in the end do not pursue a romantic relationship.

Roberts also provided the narration to many of the audiobook adaptations of Stuart Woods' novels featuring Stone Barrington, the crime-solving detective and lawyer.

His other audiobook credits include Andrew Vachss' Batman: The Ultimate Evil, Kurt Vonnegut's Cat's Cradle, and Spencer Johnson's Who Moved My Cheese?.