“Mass” takes its time letting us know what is happening and who we are watching. With his first film as writer and director, Franz Kranz begins by giving us a sense of place. We are in a church and a woman named Judy (Breeda Wool) is bustling around, a little anxious, a little apologetic, the kind of community-spirited, good-hearted soul that houses of worship rely on. A young man (Kagen Albright) is washing dishes, and we can see she is helping him by letting him help. Judy is preparing a room for some kind of event, fussing about what kind of refreshments should be provided and how the chairs should be arranged. Then Kendra (Michelle N. Carter) arrives. She is in some kind of official capacity, but it is still not clear what her role is.

And then two couples arrive. They are the ones the room has been prepared for. They greet each other cordially, but awkwardly. Linda (Ann Dowd) has brought a gift from her garden. She and Richard (Reed Birney) are somehow both together and not together. They exchange uncomfortable small talk about their children, indicating that there is some history between the four and yet they are not exactly friends and not exactly enemies.

The other couple is Gail (Martha Plimpton) and Jay (Jason Isaacs). We slowly realize that what has brought them together is an incident of unspeakably tragic (and yet perpetual) violence.

Kranz has created distinctive, believable, complicated characters and the cast is one of the best ensembles of the year. Everyone grieves differently, and those differences can drive a wedge between couples or family members who do not understand each other’s way of mourning. We see all of that here, delicately but heart-wrenchingly delineated as the various social, performative layers fall off and there is nothing left but truth and the rawest of emotion. One moment shines through like a beacon as Gail admits her fear that if she lets go of anger and resentment she will lose the connection with the son who died. The conversation ranges from the mundane to the clinical to the most viseral pain, echoing the great Auden poem Musee de Beaux Arts, and it never feels less than real and vital.

Parents should know that this is a movie about devastating pain and loss with references to the murder of children and a suicide in a school shooting and to mental illness and its impact on a family. There is brief strong language.

Family discussion: How many different ways of grief do we see in this film? How many different kinds of forgiveness?

If you like this, try: “Elephant” and “Amish Grace”