It premiered plays by Megan Terry, Sam Shepard, Jean-Claude van Itallie, María Irene Fornés and others; and it presented plays by Harold Pinter, John Arden, August Strindberg, John Osborne, Arthur Kopit, Eugène Ionesco, Berthold Brecht, Samuel Beckett and others.

Some important members of the company left, and Marlow Hotchkiss invited Sydney Schubert Walter to be the artistic director.

[17][18] In the spring of 1968, the Firehouse Theater toured Europe with its production of Megan Terry's play with music, Jack-Jack, described as a "wildly physical satire on American life."

The European tour of Jack-Jack was preceded by a seven-week run in Minneapolis, and when the theater returned it ran for another three weeks.

But at the same time it is so much like a classical painting come to life, of nymphs and satyrs frolicking on the green, that no one in Minneapolis seems to have objected loudly enough to attract the censors.

The Firehouse Theater was engaged in 1969 to present Faust,[24] which contains nudity, at St. John's University at Collegeville, Minnesota — a Catholic men's college.

Administrators at first approved, but later wanted to cancel the performance for a number of reasons, including the concerns that it might damage St. John's reputation, and might cause faculty and trustees to resign.

When the theater company returned home, the Minneapolis Tribune said they seemed "relieved that they weren’t arrested and happy that none of their performances were cancelled, though a few came perilously close.

In the original script by Brecht, Walters said, a character "shoots off his dick", The Firehouse production instead had him turn his back, cut it off, then "throw it over his shoulder as if it were a banana".

[27] The theater was known for protesting the Vietnam war from the stage, and in October 1968, the artistic director, Sydney Schubert Walter, received an induction notice from the military.