Hollywood seems to love biopics and they’re great Oscar bait, but occasionally you have to wonder what point they serve. Interesting people sometimes lead interesting lives, and interesting lives sometimes make for interesting viewing, but for a biopic to work it usually has to go beyond that – perhaps by tying into an era or a subject that most people aren’t aware of, or by introducing us to someone genuinely provocative. For me, 2004’s Kinsey – which superficially has a lot in common with The Notorious Bettie Page – hit all the right notes in that sense.

Bettie Page, by contrast, seemed to me fairly pointless, even by biopic standards. The tagline of “Good Girl. Bad Girl. Sinner. Saint. Who is . . . The Notorious Bettie Page” is a fair enough question to ask of someone who went from being ‘pin-up queen of the universe’ to preaching Christianity in the space of a few years, who came up on the radar of a 1950’s senate hearing for posing in bondage pictures and videos, and who arguably worked through the period when pornography developed from harmless smut towards modern day extremes.

But Bettie Page doesn’t come close to answering its own questions. Throughout there’s the sense that co-writer/director Mary (American Psycho) Harron has her own ideas, but that she just doesn’t want to share. I’m all for being left to come up with my own answers, but that depends on having enough information to form an opinion, and that’s something that Harron seems determined not to give us. She offers snatches of information – towards the start there’s the implication of parental abuse and soon after a gang-rape scene – but neither incident is ever referred back to, so that while we’re left to wonder what effect these events had on Page’s career choices, wondering is about all the film lets us do.

Now, perhaps this is a better than the usual biopic pretence that we can somehow understand another human being by watching certain “defining” events in their life, (Walk the Line being a recent case in point) but Harron’s approach is pretty frustrating nonetheless.

All of this is aggravated by her treating her subject with the kind of reverence people normally reserve for the newly sainted. Bettie Page is not only stunningly gorgeous, she’s a thoroughly nice person as well, and smart to boot. She works in porn to make people happy and quits when she discovers that it might not be having the salutary effects she’s imagined. Which is all well and good (and may be true for all I know), but it serves to make Bettie Page the character even more of a cipher, and Bettie Page the film even more of a non-event.

Now, I realise that I’m making The Notorious Bettie Page sound like a bad movie here, and truth be told, it really isn’t. Gretchen Mol’s central performance is tremendous – I’ve no idea if it’s accurate, but she certainly captures a range and subtlety of emotion that’s hypnotic to watch. The supporting cast are strong too, even if none of them get that much airtime. And the look of the film, part picture postcard and part fifties B-movie, is wonderful, evoking time and place beautifully.

It’s consistently watchable and absorbing, and it frequently raises interesting questions about the roles of pornography and pornographers in our society. It’s a just a shame that it doesn’t offer any answers to those questions – or about the life and career of its intriguing heroine.