Mass shootings have become tragically common over the past decade, but that doesn’t make them any easier to understand.

Claire (Neve McIntosh), a Protestant minister and the lead character of David Greig’s play “The Events,” barely survived one such catastrophe.

As she recalls it, the gunman spotted her hiding in a music room with a colleague. “I have one bullet,” he told her. “There are two of you — which one of you do you want me to shoot?”

McIntosh — barely recognizable out of the green makeup she sports as Silurian detective Madame Vastra on “Doctor Who” — is one of two professional actors in the show. Clifford Samuel handles the other characters, including Claire’s partner, Catriona, and the killer.

But there are many others on the New York Theatre Workshop stage: the members of Claire’s community choir. For each performance, they’re played by a different amateur ensemble from the tri-state area. I saw the fine Village Light Opera Group, which is based downtown.

Claire leads the singers through material as diverse as Dizzee Rascal’s grime hit “Bonkers” and a Norwegian folk song. The music adds an almost unbearable wistfulness to the show by symbolizing community and how easily it can shatter.

Greig, a Scottish writer whose well-received work includes the book for “Charlie and the Chocolate Factory,” skillfully integrates the choir and the two actors, while painting the portrait of a woman suffocating in uncomprehending anger. Claire can’t connect with Catriona anymore, and constantly rehashes what happened.

McIntosh is grimly vibrant in the role, her Claire a religious woman at a complete existential loss. In the end, though, emotional peace is possible. “We’re all here,” the choir sings. And life goes on.