A film is always the same. The images are burned into celluloid or locked onto a computer disc forever unchanged.

A play is never the same even when the playwright’s words are recited to the letter. In small ways, a production changes from performance to performance. A different director, cast and design team can alter forever the way theatergoers view a familiar piece.

For the most part, Ernest Thompson’s play, “On Golden Pond,” has belonged to the actors who portrayed Norman Thayer Jr. In the beloved 1981 film version, Henry Fonda shared billing with Katharine Hepburn but it is his quiet and dignified portrayal of old age that moviegoers remember. James Earl Jones, in a 2005 Broadway revival, created what The New York Times called a “raging Norman” unwilling to die quietly.

Penobscot Theater Company’s version of the play belongs to Barbara Haas. As Ethel, the actress exudes the love and joy that Norman, played by Barry Dunleavey, basks in. Whether it was by design or accident that director Nathan Halvorson allowed Norman’s wife to dominate the play does not matter because it works so wonderfully in the production that runs through Sept. 28 at the Bangor Opera House.

In the film and other versions of the play, Norman is the sun and Ethel one of the planets that revolves around him. Under Halvorson’s direction, Ethel provides the light and warmth that allows him to stay alive and last week delighted the audience on opening night.

An actress could decide that Ethel has surrendered her own identity to Norman’s but Haas did not play her that way. Instead, she created a woman who eats life with both hands in a joyous dance. Norman is the partner she has chosen. He’s not the man she has settled for and this is not a life she’s stuck with.

Dunleavey is a reed of a man and his physicality served his Norman well. A retired English professor, the man certainly must have been battered by the ever-changing winds of department politics. Dunleavey did not create a cranking curmudgeon or a man raging against death. His Norman was simply a devoted cynic comfortable only with emotions when they are contained within the pages of a book. He and Haas waltzed together as if they’d spent their lives portraying these two people.

Jeri Misler seemed miscast as the couple’s angry daughter, Chelsea, who appears for the first time in years with her fiance and his son in tow. It was never clear why the character was so angry and unhappy or what this charming couple did that was wrong other than give birth to Misler’s Chelsea.

“On Golden Pond” premiered 30 years ago when a 40-something daughter’s anger at the parents who didn’t change while the world around them did was understandable. By setting the play in the present, Misler was given the nearly impossible task of portraying that anger in an entirely different social context. The actress, as she’s shown in previous roles, exudes too sunny a disposition to become believably this brooding daughter.

PTC’s greatest strength — casting its shows with a mix of professional and community-based actors — also can be its greatest weakness. Kurt Massey a local teenager was delightful as the teenager Billy Ray, the son Ethel and Norman never had. Massey managed to combine the best features of them both while creating a unique Every Boy. He didn’t just hold his own with Haas and Dunleavey. As a performer, Massey, along with Arthur Morison as the delightfully dumb mailman Chelsea should have married, proved to be the equal to these veteran professionals.

That was not true of Mike Elliott, half of the 94.5 FM KISS radio morning team Mike and Mike. Elliott overplayed everything. Halvorson may have wanted Chelsea’s fiance to be a buffoon, but he’s too good a director to have chosen to make him the idiot Elliott did.

While Chelsea may have chosen to marry this dentist to bring some stability to her life, it’s unlikely she’d have settled for the fool Elliott created. Bill Ray as portrayed by Elliott made a great disc jockey but no one in the audience opening night believed he was ever a dentist, not even in laid-back Los Angeles.

Dan Bilodeau’s lovely set looked like the inside of a Maine camp well lived-in and it served the action well. Lynne Chase’s lighting design signaled the time of day and the passing seasons better than any dialogue or setting notes.

It’s hard to discern what Producing Artistic Director Scott R.C. Levy was saying about the theater company’s future or its past by choosing to kick off PTC’s 35th season with “On Golden Pond” other than to offer the comfortably familiar to area theatergoers. Under Halvorson’s direction, however, the now classic play managed to offer up a few surprises thanks in large part to Haas’ dynamic performance.