Michael Boatman (“Spin City”) and Michael Therriault will topline the Roundabout’s upcoming Off Broadway tuner “The Tin Pan Alley Rag.”

Boatman will play Scott Joplin and Therriault, who played Gollum in the West End and Toronto incarnations of the “Lord of the Rings” musical, will portray Irving Berlin in the show, which imagines a meeting between the two musicians.

“Rag,” helmed by Stafford Arima (“Altar Boyz”), will incorporate Joplin and Berlin tunes into its story, penned by Mark Saltzman (“Sesame Street,” “A, My Name is Alice”).

Also in the cast are Jenny Fellner (“Pal Joey”) and Michael McCormick (“Curtains”), among others.

Production begins previews June 12 ahead of a July 14 opening at the Roundabout’s Laura Pels Theater.