Emmy winner and three-time Tony nominee Shalhoub joins a cast that also includes Mary Elizabeth Winstead, Aaron Tveit, Danny Pino and Nikki M. James.
The series, which will make its debut this summer, is from the creators and executive producers of the CBS hit "The Good Wife," Robert and Michelle King.
In "BrainDead," according to the industry website, "Laurel (Winstead), a young, fresh-faced Hill staffer, gets her first job in Washington, D.C. to discover two things: The government has stopped working, and alien spawn have come to earth and eaten the brains of a growing number of Congressmen and Hill staffers."
Shalhoub has been cast as Red Wheatus, who is described as "a hard-drinking, fun-loving Republican senator who has spent decades in Washington making deals, until a radical transformation turns him into a health-conscious extremist who would rather destroy the government than compromise."
Shalhoub was Tony-nominated for his performances in Act One, Golden Boy and Conversations with My Father.