The Unknown Girl (15)

Curzon Artificial Eye, £15.99

Double Palme d'Or winners Luc and Jean-Pierre Dardennes are best known outside their Franco-Belgian stomping ground for Two Days, One Night, which won Marion Cotillard an Oscar nomination in 2015 for her performance as a desperate young mother with two days to save her factory job. As with that film, 2016's The Unknown Girl follows a single-minded young woman on a mission and is set in the same area, the industrial towns around the Dardennes brothers' home city of Liege.

This time it's someone at the other end of the professional spectrum - Dr Jenny Davin (Adele Haenel), a GP who fails to answer her practice door late one night (she's already an hour past closing time) and as a result finds herself embroiled in a police investigation into the death of a young black woman.

Footage from Davin's own CCTV camera shows that it was this woman who rang the doorbell. From the fleeting image available, it looked like she was being chased and needed somewhere to hide. But the police have no name for the dead woman and nobody has reported her missing, so she's buried, nameless, in an unmarked grave The guilt-ridden Davin sets out to put a name to her, a quest which takes her into the seamier side of her patients' lives and of Liege itself.

The magnificent Haenal is in every scene to the extent that she is every scene: the Dardennes' camera follows her closely as she fearlessly and doggedly pursues leads, making phone calls to the police in between visits to patients and showing a relentlessness that puts the cops to shame. Davin's inscrutability make her a difficult character to read or even like, but that doesn't detract from the wider issues The Unknown Girl broaches, notably human trafficking and (a Dardennes brothers fave) Belgium's underclass. A gripping film made all the more impressive for its studied lack of drama.

Deep Water (15)

Peccadillo Pictures, £9.99

Inspired by a series of murders which targeted gay men in Sydney's Bondi Beach area in the late 1980s and early 1990s, this four-part miniseries dramatises a modern-day police investigation into a similar spate of historic hate crimes. It screened in BBC Four's traditional Saturday noir-ish foreign import slot but in Australia it aired as part of a wide-ranging investigation by state broadcaster SBS into the real killings, now thought to number around 90, which included a hard-hitting documentary featuring testimony from survivors and interviews with police officers.

That background goes some way to explaining the awkwardness of the production itself: neither entirely fictional nor able to use real life stories due to the ongoing sensitivities surrounding the case, it ends up picking a line between the two and lacking dramatic punch as a result.

At the heart of the story is investigating office Tori Lustigman. When she spots a possible link between a fresh murder and a similar but unsolved crime from 1990, she starts to dig deep. She has personal as well as professional reasons for doing so – her elder brother died around the same tine, apparently drowned while swimming. But is that the real story? Despite all that, Lustigman (as played by Yael Stone) is a peculiarly un-engaging character, another problem for Deep Water's ability to grab the viewer. Thank heavens, then, for one time Neighbours star Craig McLachlan (as unpleasant club owner Kyle Hampton) and, in particular, for Noah Taylor, as Lustigman's laconic and world-weary partner Nick Manning.

The 9th Life Of Louis Drax (15)

Soda Pictures, £19.99

Adapted by Max Minghella from British writer Liz Jensen's novel of the same name, Alexandre Aja's film tells the story of Louis, a boy so accident prone he seems to spend much of his life in hospital. His loving, beautiful, blonde mother Natalie (Sarah Gadon) tells him he's used up eight of his lives already but it's on a picnic with her and her estranged husband Peter (Aaron Paul) that Louis has his closest brush with death when he falls over a cliff. The film opens with Louis in mid-fall, narrating what seems like his own demise and giving us a potted history of his life so far.

In the aftermath, Louis is pulled from the sea and pronounced dead but then miraculously comes back to life before falling into a coma. Enter handsome (and married) coma specialist Dr Allan Pascal (Jamie Dornan, in his first post-50 Shades outing). Meanwhile, Peter Drax has disappeared so the police investigation (and everyone else) goes along with Natalie Drax's story: that after rowing with her, a drunk Peter threw Louis over the cliff as she tried to save the boy.

So far, so noir-ish and femme fatale-ish. But increasingly the film dips into Louis' subconscious, where he converses with a gnarly, gravel-voiced sea monster that could have stepped straight out of Pan's Labyrinth (Frenchman Aja is most notably a horror director). Pascal also finds himself having dream visions in which the same creature features, and eventually comes to the chilling conclusion that the comatose Louis is somehow able to use him as a conduit for paranormal communication.

In outline, it's a decent plot – thank Jensen for that – but Minghella's creaky script does nobody any favours and too many characters are inked in so lightly they might as well not be there while others feel like they've walked in from a different film entirely.