The new "Married Couples" episode will also include Kat Nejat and Ben Thompson.
The spring performances will be broadcast on PBS.
Foster is now performing at Broadway's Schoenfeld Theatre in The Bridges of Madison County.
Tony nominee Isabel Keating will accompany the Broadway bad guy in his one-night-only performance.
The two actors, who also wrote the new musical, will reprise roles they originated at New York's Soho Playhouse in 2012.
Tony nominee Scott Wentworth will direct and perform in a Main Stage production of '''Much Ado About Nothing''.
Barrett will reprise his long-running role as lawyer Billy Flynn.
The Tony winner will share his tips for adding theatrical touches to your home.
Trip Cullman will direct the drama in April.