“Never wear your favorite trousers when you go out to fight for freedom and justice,” warns Dr. Thomas Stockman in Henrik Ibsen’s autobiographical tour-de-force, “An Enemy of the People.”

This classic play is the story of a spa town where the major sources of income — public baths — have become infested with poisonous bacteria. Upon making the discovery, Dr. Stockman, strikingly portrayed by four-time Tony Award-winner Boyd Gaines, goes to work trying to convince the town to shut the baths down.

But the people will not listen. Instead they buy into the cost-effective lies espoused by the mayor, who also happens to be Dr. Stockman’s brother.

The doctor and his family are run out of town, but Stockman never wavers in his convictions, holding on to the ideal that it is important to take a stand, even if that means standing alone.

Dr. Stockman is widely viewed as a dramatic embodiment of Ibsen himself, whose work was often criticized as scandalous. “An Enemy of the People” was itself written in response to the horrified reception that greeted the playwright’s previous work, a play called “Ghosts.”

Gaines’ performance does justice to the playwright’s fiery words — and then some.

“Every single exclamation mark stays,” he bellows about the passionate punctuation in his report on the baths’ contamination. “If in doubt, add more.” This statement is delivered towards the beginning of the play when the doctor’s reputation remains unsullied, and Gaines flies about the stage in near-boyish fervor over his discovery.

The actor’s transformation of the character throughout the play is masterful. At the end of the play, he carries himself with slumped shoulders but an upturned chin. Gaines presents the stature of a man who knows he has lost but refuses to submit.

Opening just a little over a month before election day, the Manhattan Theater Club’s revival has the sought-after element of relevance, expressing bold ideas about the ignorance of the majority and the corruption of politicians.

Early on in the play, one character insists, “All the same, one ought to vote at any rate,” to which another replies, “Even if one doesn’t know anything about what is going on?” Moments like these hit especially hard this time of year.

“An Enemy of the People” is playing an open run at MTC’s Samuel J. Friedman Theater, 261 W. 47th St. For tickets and more information see anenemyofthepeoplebroadway.com.

A version of this article appeared in the Tuesday, Oct. 9 print edition. Olivia George is a staff writer. Email her at [email protected].