At more than 90 years old, director Don Stolz knows well the vagaries of age, its losses and diminishments. But he also has a warm heart and an indomitable spirit. These traits are all very much in evidence in his production of "On Golden Pond," currently running at Old Log Theater in Excelsior.

Ernest Thompson's play about Norman and Ethel Thayer's 48th summer at their vacation home on Golden Pond in Maine is as warm and sentimental a comedy as the title seems to imply. Norman is turning 80 and is beginning to seriously slow down, the focus of the play's humor and its drama. When he and Ethel become custodians of their daughter's boyfriend's son, important lessons are learned.

For all its popularity, this is not a particularly good play. It's overly talky, the exposition is often clunky and some of the dialogue is cringe-worthy. But it's primarily a vehicle for actors, providing the fodder for great performances. At this, Old Log delivers.

Steve Shaffer gives the performance of a lifetime as Norman. He has made a career of broad, over-the-top characters. But here, he is subtler and more fragile than past performances might suggest. The dry wit that he brings to the irascible curmudgeon is great fun, but he does not stint on the darker aspects of this angry, bigoted old man. And his recognition of his own decline is deeply affecting.

As Ethel, Nancy Marvy is endearing, but initially too dotty and congenial, as if trying overhard to be liked. In the second act, she develops a toughness that makes her confrontation with her daughter sizzle and her final scene with Norman far more heart-rending than the script has any right to expect.

But Elizabeth M. Desotelle is overly whiny as the daughter. And Bryan Dobson, as her boyfriend, and John Elsen, as the mailman, have thankless jobs: Their roles have less to do with characters than with filling time for action happening offstage. But they make the most of their comic moments. Lucas Bolstad, as the smart-alecky boy, held his own partnered with Shaffer.

Jon C. Stolz's stunning set of the summer home offers an eye-catching frame for Stolz's simple and unfussy direction. He is a master of the many comic moments, but also plumbs the darker emotional depths. He gives the production a nostalgic, even valedictory feel.

William Randall Beard writes regularly about theater.