This wildly entertaining film accomplishes what only the best docs can do: takes you inside human obsessions and illuminates them.

In this case, the obsessor is long-time David Letterman writer Steve Young, who stumbled onto arcane LPs for a Late Show bit and then plunged down the rabbit hole of “industrial” musicals—fully-fledged productions created only for a corporate audience. (The title refers to “The Bathrooms Are Coming!”, the lodestar of this weird subgenre.) From the few artifacts remaining, he discovered that some were actually good, and also gave a foothold to struggling composers and performers, with people like Martin Short and Florence Henderson (seen here) getting early-career paychecks from them. Director Dava Whisenant, herself a veteran editor of Late Show and other TV series, couldn’t have known where this would lead, so it’s doubly satisfying when Young’s compulsion ends with much deeper human connections. And very satisfying fun for the audience.