Massey, 33, will be portraying an openly gay and successful country music star named Kevin Bicks, reported Deadline.
The arrival of Kevin Bicks in Nashville will cast doubt on closeted Will Lexington's (Chris Carmack) belief that gay country singers must hide their sexual orientation in order to be accepted.
Massey has appeared on the Broadway stage in 'West Side Story', 'Pippin' and 'Wicked'.
This season, 'Nashville' has introduced Derek Hough as an actor researching country music for a role and Mykelti Williamson as a local homeless man.