The Bill

ITV1, 9pm

It’s all change down at Sun Hill Instead of going out twice a week at 8pm, The Bill will now be going out once a week at 9pm on Thursday. This reduces the number of episodes a year from 96 to 52, halves the production team, cuts down on the actors and saves ITV heaps of money. But change, we are told, is good. The new-look Bill is shot in high-definition, and the iconic theme music has been replaced with something slower and more thoughtful. “We haven’t sought to totally reinvent The Bill,” says the executive producer Johnathan Young. “We’re digging deeper into characters to tell stronger and more challenging stories which examine the true causes and effects of crime.” This leaner, sleaker format kicks off tonight with a special double bill centred around a violent assault on a 15-year-old boy on a council estate. It concludes at the same time tomorrow night.

Headshrinkers of the Amazon: Revealed

Five, 8pm

In the 1960s, the Polish film-maker Edmundo Bielawski ventured into the far northwest of the Amazon rainforest and filmed the Shuar tribesmen shrinking a human head. The skull was removed and the head filled with hot sand and then boiled. It was intended to punish the evildoer and ensure that his vengeful soul was rendered powerless. If genuine, the 1960s footage is the only such film known to exist. In this informative documentary, the writer Piers Gibbon follows in Bielawski’s footsteps to see if he can authenticate it.

The World’s Oldest Mums

Channel 4, 9pm

The story of Elizabeth Adeney, the 66-year-old divorcée who gave birth earlier this year, created an almighty furore in the press. One journalist called the image of mother and child “a sickening picture that makes me shudder”. But with everyone living much longer and women still battling for equal rights, who is to decide the cut-off age for motherhood? When the film-maker Amanda Blue began interviewing four new mothers with an average age of 70, she didn’t know how she felt. “My aim was to go beyond the knee-jerk reaction of the media, to meet the women who’ve pushed against the boundaries set by nature and society.” And what did she discover? “My feelings and empathy for the women oscillated constantly during the filming. It was hard to ever draw black-and-white conclusions.” You decide.

Psychoville

BBC Two, 10pm

It’s the penultimate episode of a series that shows no signs of returning to Planet Normal any time soon. All the characters are worried that their mysterious blackmailer is “deeply disturbed” and “bordering on the psychotic”, which brings to mind pots and kettles of the blackest variety. As the story unfolds, they are all drawn to a disused hospital in readiness for a macabre showdown. But before that can happen, the Mother & Son team of serial killers (Reece Shearsmith and Steve Pemberton) are preparing to dispatch one final victim. Mum wants to buy an indoor barbecue in readiness for the occasion. “I thought we could do something special,” she says, “and eat her. What do you think? I’ve bought some red onions.” “That’s disgusting,” her son replies. “I don’t like red onions.”

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