The opening film for this year’s Tokyo International Film Festival seems better suited for a weekday matinee screening at a second-run theater. Junji Sakamoto’s “Climbing for Life” is a perfectly watchable biopic that mostly avoids corniness, but it can’t resist the gravitational pull of its star, Sayuri Yoshinaga.

The 80-year-old actor (making her 124th screen appearance) is a national institution in Japan — though she doesn’t enjoy the same recognition overseas. “Climbing for Life” is unlikely to change that: While it’s more restrained than the tearjerkers that have defined Yoshinaga’s career, it’s just as old-fashioned in its sensibilities, redolent of Yoji Yamada’s heartwarming dramas.

Yoshinaga plays Junko Tabei, who in 1975 became the first woman to summit Mount Everest as part of an all-women Japanese team. Riko Sakaguchi’s screenplay weaves an account of that expedition into a story focusing on the final years of Junko’s life, after she is diagnosed with terminal cancer. Refusing to go out without a fight, she starts organizing trips to Mount Fuji for high school students affected by the Great East Japan Earthquake of 2011.