After debuting at the Toronto International Film Festival, the tear-jerker has taken a year and a half to reach theaters. It's about cancer, which is probably a strike against it. One of its three stars is Casey Affleck, who has been dogged by allegations of misconduct and a public non-handshake from Brie Larson when she handed him his "Manchester by the Sea" Oscar. And it's the sort of small, tender story that used to sweep movie awards but has been more likely to show up on TV in recent years.

But it is not your standard disease-of-the-week affair.

"Our Friend" is based on journalist Matt Teague's essay, which he thought would be about his late wife, Nicole, but morphed into a tribute to their friend, Dane. He helped them in unprecedented ways when Nicole (Dakota Johnson) was diagnosed with cancer and Matt (Affleck, understated) was traveling for work so often that neither of them could adequately care for their two young daughters. Enter Dane (Jason Segel), then Nicole's friend more than Matt's, who moved in with them to become a full-time child care/health care/best friend ever, with an additional dose of awkwardness because he once asked Nicole on a date and was probably still attracted to her.

That last detail is a key to why "Our Friend" is so good. It feels scrupulously honest in its depiction of both Nicole's illness and the family's response to it, and that means it makes room for details that don't fit a tidy narrative arc. The Teagues' friends, for instance, do not understand what Dane is doing there, implying that he's a freeloader or worse. At the point where it seems "Our Friend" is on the verge of canonizing Nicole as a generous friend and warm, dedicated mom, her harsh medications do so much damage to her system that she begins to seem possessed, spewing hate at the very people who are trying to make her comfortable. Segel, of whom I've never been a big fan, is particularly good in this scene, patiently absorbing the blows while remaining in caretaker mode.

It's not an easy movie to watch, but the other thing about honesty is that it draws us in. Directed by Gabriela Cowperthwaite, whose biggest credit is the excellent SeaWorld documentary exposé "Blackfish," "Our Friend" inspires trust. Because of its truthfulness, we're willing to stick through the hard stuff, confident that there will be beautiful stuff, too.

A lot of that comes from Johnson, whose brightness and humor before Nicole gets sick (the movie is non-chronological, to good effect) remain vivid in our minds even near the end. She and Segel are both funny, and "Our Friend" is always willing to find humor in painful moments, which feels honest, too. Then, just when I thought I couldn't like this movie more, the great Cherry Jones shows up as Nicole's hospice worker.

Jones' clear-eyed forthrightness gets "Our Friend" to the finish line and makes sure that, as much as it's a movie about cancer, it is even more about friendship, kindness and love.

Chris Hewitt • 612-673-4367

Our Friend
⋆⋆⋆½ out of four stars
Rating: R for language.
Where: In theaters and on demand.