An eccentric Danish inventor builds his own submarine and takes it out into the Baltic. With him is a female Swedish journalist, who’s writing a feature about him. The sub mysteriously sinks. The Dane is rescued, but there’s no sign of the journalist. He claims he put her off on an island, but later changes his story – to what we don’t know; the police are keeping stum – and she’s nowhere to be found. They search the sunken sub, and find no trace of her there, but do find evidence that he may have sunk the sub deliberately. The Danish police arrest him for suspected murder. All news dries up – Danish sub judice rules, one assumes. In the meantime it’s revealed that he’s also working on a private space rocket, which may be relevant – we don’t know.
A case for the old Kurt Wallander, surely? Or does it seem too far-fetched? But it’s all true. (Google it. The submariner’s name is Peter Madsen.)