Theater

‘The Old Friends’ has benefits

Not a season goes by without a Horton Foote play or three. Like clockwork, “The Old Friends” opens at Signature just as “The Trip to Bountiful” enters the last stretch of its Broadway run.

One reason why Foote’s proved so popular is that he wrote deceptively simple characters who turn out to be gifts to actors — and, by extension, audiences.

Such is the case again with “The Old Friends,” in which a virtuoso ensemble led by Betty Buckley and Lois Smith delivers a master class in precision acting.

Written in the 1960s, then revised over the next 40 years, the show offers a different vibe for Foote fetishists. The late playwright’s balance of gentle compassion and decency is in evidence, but he also whips out the claws. Frustration and rage occasionally burst through. There’s even a gun — and it goes off!

The trigger, so to speak, is the return of Sybil (Horton’s daughter Hallie Foote) to her hometown of Harrison, Texas. Following the unexpected death of her (unseen) husband, the impoverished Sybil is thrown in the middle of a power struggle between her elderly mother-in-law, Mamie (Smith), and Mamie’s other child, the wealthy Julia (a drolly grand Veanne Cox).

Even richer is Gertrude (Buckley), a widow who loves vodka and bossing people around, including her stoic business manager, Howard (Cotter Smith), for whom she hankers.

Several scenes are uncharacteristically showy for Foote, especially when the characters booze it up — which they do often.

Drunk scenes can easily careen out of control, but the cast shows exemplary restraint and finesse under the direction of Michael Wilson, who also helmed the current “Bountiful” revival.

Smith brings ramrod-straight dignity to Howard, while Lois Smith is heartbreaking as always — even if she soft-pedals her prickly character, who prompts an outburst from Julia’s submissive husband, Albert (Adam LeFevre). “I hate old times,” he coldly tells Mamie, “and I loathe you.”

But it’s Buckley who runs this roost, looking simultaneously imperial and fragile in David C. Woolard’s impeccable ’60s costumes.

During one of Gertrude’s binges, she goes through emotions with quicksilver virtuosity. Calling Julia a whore, Buckley stretches the word to a roar.

A few beats later, Gertrude’s pleading with Howard: “Maybe you will love me some day if I behave myself,” she says abjectly. “Will you love me if I behave myself?”

When the right actor delivers such simple words, they’re transcendent. And that’s why Horton Foote plays keep getting produced over and over.

elisabeth.vincentelli@nypost.com