Torchwood: Children of Earth

BBC One, 9pm

Fans of Torchwood are in for a treat. This mini-series, written in part by Russell T. Davies, starts tonight and continues over the next five nights. Preview tapes were available for the first three of the five episodes, so I can safely say that, having got off to a strong start, it gets better and better. The story begins when every child in the world stands stock still and announces, in unison, the imminent arrival of creatures from space. That would be alarming enough, even without the British Government getting involved in a cover-up to hide the fact that these creatures had visited Earth before. And for the cover-up to work, they need to get rid of Captain Jack (John Barrowman) and his crew. This is Torchwood at its best — imaginative, exciting and funny. It also includes a jewel of a performance from Peter Capaldi as a twitchy civil servant, the polar opposite of his swearing media fixer in The Thick of It.

Teenagers Fighting Cancer

Channel 4, 8pm

James House’s film about teenagers receiving cancer treatment at Queen Elizabeth Hospital in Birmingham is the most draining programme I’ve ever watched. The emotional intelligence and matter-of-fact courage of the teenagers and their families — and of the medical staff who help to carry the weight — is overwhelming. Here is one girl, for example, the night before radical surgery. “It’s like waiting to go on a big ride,” she says. “You’re really excited to go on it, but at the same time you’re so scared.” But why would anyone choose to watch a programme like this? Because it would be impossible to watch without being changed in some way for the better.

Inside Nature’s Giants

Channel 4, 9pm

It was never like this in biology classes. Tonight’s episode of this richly informative series features the dissection of a 65ft, 60-tonne fin whale that died after it was stranded off the coast of Ireland. Dissecting whales — like elephants — comes with its own unique set of challenges. Whale anatomist Joy Reidenberg flies in from New York in the hope of arriving before the whale explodes on the beach as a result of decomposition. The team have to splosh around in blood and intestines, wielding their supersize scalpels while buffeted by gale-force winds and freezing rain. They chop, slice and saw to find out why this particular whale died, and to demonstrate how these Leviathans evolved from land-based mammals into vast swimming hippos. Next week, the crocodile gets it.

Hannah’s Killer: Nowhere to Hide — Real Crime

ITV1, 9pm

By every account 17-year-old Hannah Foster was exceptional — an attractive, bright and much-loved student intent on becoming a doctor. In March 2003, she was raped and murdered in Southampton by Maninder Pal Singh Kohli. It didn’t take the police long to identify her killer, but he fled to India and assumed a new identity. Instead of giving up hope, Hannah’s parents flew to India and gave an emotional press conference, appealing directly to the Indian people for help in finding her killer. It became headline news, and he was picked up while they were still in the country. More than 100 court appearances and 30 appeals later, her killer was extradited to Britain. With contributions from the police in Britain and India, the film bears witness to the triumph of tenacity and justice.

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