The Mystery Play is a detective story, a ghost story, and a memory play: a theatrical blending of Wit and The Woman In Black. Though fully self-contained, The Mystery Play is also the second in a trilogy about crime-solving Sister Vivian Salter, a flinty, fifty-ish Catholic nun forced into the role of amateur sleuth. Each story in her trilogy was penned by a different playwright and commissioned by Ship's Company Theatre in Parrsboro, Nova Scotia.

, Salter recounts her late-stage struggles with her own beliefs while also detailing her father George's descent into Alzheimer's. In his seventies, George is becoming prone to semi-violent outbursts, to speaking with phantoms in the middle of the night, and to eerie sleepwalking all of which leave Salter exhausted and questioning the existence of God's love. Then, into the adjoining suite next door moves a young schoolteacher, Jennifer Craig, and her husband, Peter. This newlywed couple seems perfect, and very much in love ... until they don't. By creeping attrition, Salter begins to suspect that terrible spousal abuse is taking place next door, and, despite herself, she gets drawn into mystery once more. But this time it's a fearsome mystery that sneaks increasingly closer and closer to home.

, a supernatural chiller of rattling cupboards, overnight sances, and spectral possessions, reveals a new definition of "mystery" one derived from the Mystery Plays of sister Salter's dwindling faith in which the word can also mean a miracle beyond all logic.