A good murder goes a long way. Something weird and gruesome that sticks in the memory. The body placed directly on the Danish / Swedish border in The Bridge; the displayed ritualistic cadavers from True Detective; Paul Spector (Jamie Dornan) meticulously washing then posing his victims in The Fall are all perfect examples that instantly hooked audiences. And Witnesses: A Frozen Death starts with a real kicker: 15 frozen corpses found seated on an abandoned bus in northern France.

The vehicle was stolen two weeks ago and Lieutenant Sandra Winckler (Marie Dompnier) soon discovers the dead men all had links to a woman named Catherine Keemer (Audrey Fleurot) who has been missing for three years. Curiouser and curiouser. You can't help but wonder how in the hell this crime was committed, let alone why?

In case you are wondering where you might have seen Witnesses before, the first series screened on Channel 4 in 2015, now finding a new home on BBC Four in its regular Saturday night international thriller slot (with two episodes airing every week). A Frozen Death is a completely new and unrelated case so feel free to jump on here.

Witnesses is nicely paced with judiciously timed reveals and cliffhangers. Dompnier is a decent lead as the determined detective struggling with the pressures of being a single parent, but the case is the star here. However there's no point having a great premise if you don't know where to go next. And we've been burnt before; the first season featured a similarly intriguing starting point (dead bodies arranged in a show home) then quickly ran out of steam.

Explaining away a crime as bizarre and grandiose as this can lead to a convoluted conclusion that stretches the realm of credibility. Three episodes in, we're still hooked and hope the finale can match the brilliant, macabre beginning.

Witnesses: A Frozen Death starts on BBC Four, Sat 25 Nov, 9pm.