For five decades, Tom Skerritt has played key supporting roles in some indelible films — from Robert Altman’s revolutionary comedy M*A*S*H to Ridley Scott’s sci-horror masterpiece Alien to Tony Scott’s Tom Cruise–powered action-star watershed Top Gun. The man does seem to have an uncanny ability to pick projects that will have a long shelf life — everything from Up in Smoke and Harold and Maude to Singles, Steel Magnolias, Poison Ivy, and Contact. But in recent years, the actor, now 88, has appeared in several leading roles. His most recent film might contain his greatest performance to date. In director S.J. Chiro’s moving East of the Mountains, based on the novel by David Guterson, Skerritt plays an aging, retired doctor consumed by grief, illness, and regret, who struggles to find a reason to keep on living. When he goes on a hunting trip with his dog, however, he finds himself confronted by not just his own frailty, but also the kindness (and in some cases, the cruelty) of others. The subject may sound grim — and it is — but the movie itself is gentle and lovely, partly because of Skerritt’s marvelously subtle performance, which reminds us of what a fine actor he is. Indeed, the chance to watch Tom Skerritt for the full length of a feature film, especially nowadays, feels like a rare gift. I recently talked to the actor about his new film, his approach to acting, his own regrets, his memories of his most iconic roles, and how Robert Altman helped save him during one of the darkest periods of his life.