In 18th-century Manchester, an illiterate woman who had suffered four infant deaths spun off a utopian Protestant sect that came to be known as the Shakers for their boisterous sin-cleansing chanting and dancing. Its basic tenet was the idea that recreational sex is evil. She started referring to herself as “Mother Ann” and then declared that she was nothing less than the second coming of Christ. The sect eventually washed up on American shores, where it found a brief but innovative following before dying out (I’m thinking the sex thing).

Fair warning, critic-recusal dept.: You may want to seek out – how to say it? – a less cynical reviewer who’s not quite so atheistic before deciding to pay money to see this biopic by Norwegian auteur Mona Fastvold. Oh, from an artistic and technical standpoint, it’s quite the brilliant achievement. Amanda Seyfried puts in a career-best in the title role, and that’s saying something. The singing (yes, it’s a musical) fits the story, and the rousing dancing bits had even me wanting to join in.

But the problem with auteur biopics is that they are usually more about the director than they are about the subject, and the narrative suffers. Also, unwavering fanatics don’t often make the best protagonists. So while this film is certainly impressive, it’s not what you’d call entertaining. Forgive me, but instead of feeling awe, I found it more evocative of those YouTube sites like Culture Catz that debunk (well, mostly make fun of) all those flat-earthers, heaven-visitors, UFO abductees and multilingual alien tongue- babblers out there. Or maybe Money Python.

Yes, I watched it all the way through, albeit in three or four sittings, and brothers and sisters, I’m here to testify that this is one overwhelmingly self-serious, holy slog. (136 min)

Out in theatres now