At South Coast Repertory, Matthew Arkin teaches, coaches and acts

Matthew Arkin has less than an hour before he is to appear in character on South Coast Repertory’s stage, and he needs caffeine.

It just can’t make him burp.

“Help me,” he says straight-faced to a Starbucks barista at South Coast Plaza. “I’m performing tonight.”

The barista suggests a Nitro Cold Brew, a treat that’s straight from the tap and topped with a float of house-made vanilla sweet cream.

“Some day,” Arkin, 57, begins singing to a blushing employee, “When I’m awfully low, when the world is cold, I will feel a glow just thinking of you, and the way you look tonight.”

Customers turn toward him and start to laugh.

“See the show tonight!” he implores, walking out of the shop.

He’s been making audiences smile for some time.

Arkin, the son of Jeremy Yaffe and actor Alan Arkin, is the director of South Coast Repertory’s Acting Intensive Program, a seven-week summer training program for career-minded students. He’s also taught at the HB Studio in New York City and at the Actors Studio in Los Angeles.

The program, established in 1970, was designed to provide students with a candid and comprehensive assessment of the abilities they bring to class and create a plan to guide them toward career paths.

Graduates — Will Ferrell, Arye Gross and Alison Case among them — have appeared on South Coast Repertory’s stages and in film, television and theater across the country

At the conclusion of the program, students present a showcase before an audience of theater and industry professionals. Arkin has led the program for more than two years and his relationship with the Tony Award-winning regional theater started about eight years ago.

Arkin played the 600-pound Charlie in the repertory’s West Coast premiere of Samuel D. Hunter’s “The Whale,” earning him critical acclaim.

Last year, he was in Robert Schenkkan’s Tony- and Drama Desk Award-winning “All the Way.”

He’s appeared on Broadway in “The Sunshine Boys,” with Jack Klugman and Tony Randall, and received a Drama Desk nomination when he originated the role of Gabe in Donald Margulies’ Pulitzer Prize-winning “Dinner With Friends,” for which he also was a Drama League honoree.

But all the acting success came after he made the decision to leave law, a profession he originally thought suited him best.

One summer during his childhood his parents took him and his brothers on set to Vermont for two weeks. Arkin, an avid reader, met a new teacher who gave him a copy of “To Kill a Mockingbird” and taught him the lessons in the book.

The themes of morality and reason resonated, and the novel’s protagonist, Atticus Finch — a lawyer — became a mythic hero to Arkin.

But after five years of practicing law with small firms in Tarrytown and White Plains, N.Y., Arkin, then 29, quit to pursue a career in acting. While auditioning for roles, he worked as a bartender and taught classes in public speaking to fellow attorneys in need of continuing education hours.

His father — who has twice been nominated for the Academy Award for Best Actor and won one of two Academy Award for Best Supporting Actor nominations — met the decision with complicated feelings, Arkin says.

His parents worried about him facing the difficulties in the industry known for its rejections, but Arkin began getting enough work to make a successful career, having performed in films and television shows including, “All My Children,” “Liar, Liar” and “Law and Order.”

That constructive thinking is what Arkin says he passes onto students who wish to become rich and famous, thinking acting is a fantasy life.

Too many acting classes focus on getting the job, but don’t instruct on how to do the job, he says.

“You don’t get to the fun part without doing the difficult work of learning your lines,” Arkin says with a laugh, noting students must be attuned to the possible realizations of the script.

“Acting is about trying to get what you want,” Arkin says. “I hope students learn how to be present, spontaneous, honest and emotionally available and I also hope they learn how to read.”

kathleen.luppi@latimes.com

Twitter: @KathleenLuppi