Hey book fans, do you remember Room? It was Emma Donoghue’s 2010 novel about an abducted young woman rearing her five-year-old, the product of being raped by her captor, in the fortified shed he’d imprisoned her in. Sure, you do. You remember being irritated by little Jack’s narration, his occasional lapse into adult understanding, replacing the junior literalism present elsewhere, his references to having a “silly penis”, his annoying description of everyday objects, and let’s not forget, his memory – terrible in places, acute in others, as the plot demanded. Do you remember thinking that a movie would solve these defects? Because then you’d have the child’s perspective without the problematic words. We’d still see the world through his eyes – low camera angles, grabs of adult conversations, blurry POV aping eyes adjusting to natural light, but we wouldn’t have to worry about his vocabulary or the authenticity of his subjectivity. No, we’d just watch him talking to his mother, listening, shouting, crying, muddling along, and maybe it’d be touching. Maybe it would work.

Well, good news. Emma Donoghue’s Room screenplay does all of the above, keeping what’s good about her Joseph Fritzl/Ariel Castro-like kidnap ordeal and escape drama, and excising the creaky elements. For once the limitations of film make for a more convincing spectacle as the audience gets to project their imagined understanding of Jack and Ma’s plight, rather than having words put in the boy’s mouth. Lenny Abrahamson’s direction keeps the action tight, intimate and character focused. Consequently, you get an archetypal solid, award baiting drama, that polishes up a half-decent novel, making a good if unexceptional movie.

The nature of Room, a story that seeks to mine plenty of pathos from the forced incongruity of horrors understood by adults refracted through the prism of childhood innocence, means that inevitably something is lost. That something, which Donoghue again chooses to lose in her movie adaptation, is a tighter focus on “Ma”, played with a great deal of conviction by Brie Larson. She’s a woman that’s been imprisoned for 7 years, made pregnant, forced to raise that child in captivity, and is raped nightly by her captor, “Old Nick”; a woman with a story to tell who’s denied the chance, both novel and film deferring to her young son.

Occupying Ma’s subjectivity, understanding why she chooses the moment she does to plan an escape, would have made for a highly compelling narrative. Does she think about the potential danger to Jack when Nick realizes it’s no longer practical to keep them both? Has she thought about what Nick will do when it dawns on him that Jack, for those same logistical reasons, can’t grow up – that he can’t hope to control a grown man bonded to his mother? Is Jack, her rock and focus, now becoming a liability for them both? What would be the emotional fallout for a mother contemplating such a thing? Is that what prompts the escape attempt, or is it just Nick losing his job and potentially not being able to look after them both that signals enough is enough? We don’t know in the novel and we don’t know here. And that, the real victims of similar setups would surely say, is a shame, because that’s where the meat of the human drama lies. Not in a child’s lack of understanding but an adult’s fully cultivated, stark awareness of their situation and the likely horrors to come. But Donoghue, in the interests of stoking cheap sympathy from her audience, using the well-leant on crutch of child innocence, leaves all of this to our imagination. Fine, but the story’s stripped of some of its power as a consequence. It’s practically sanitized.

So Room, though an improvement on the source novel, remains a prisoner of its limited point of view. All storytelling is a choice of course – you decide whose tale to tell, what to share and what to hold back. But for the most part, the darkest corners of Room remain unexplored – Ma’s mindset, the fraught relationship between her parents, Old Nick’s subsequent trial and justification for his actions. All of this, perhaps, requires a great deal of harrowing imagining – going to some very dark places – but visiting them might have made Donoghue’s story essential rather than quietly moving.

Related: Room: The Novel Review (2010)