TV tonight: Emily Watson stars in the blockbuster Dune prequel

Dune: Prophecy Emily Watson stars in this big-budget prequel to the blockbuster films, which is set more than 10,000 years before Timothée Chalamet arrives on the scene. She plays Valya Harkonnen, the mother superior of an order on Wallach IX, who vows to protect the Sisterhood (which will become the Bene Gesserit, the superhuman, all-female "mental and physical school") alongside her sibling, Tula ( Olivia Williams ). Thirty years later, a royal wedding, which is part of their plan, comes under threat. Hollie Richardson

Panorama: Can Scientists Save the World? Carbon-absorbing mechanical trees? Cloud-brightening machines? These are just a couple of the innovations that the reporter Richard Bilton investigates as he meets the scientists trying to find solutions to the climate crisis. They claim that they work, but need investment to be effective on a mass scale.

Immigration: How British Politics Failed The concluding episode is a bumpy trip down memory lane in one of Theresa May's "go home" vans , as we revisit the "hostile environment" policy and Ukip's rise. Several key players are interviewed, but will anyone suggest that immigrants have been scapegoated for a more fundamental failure of politics? Ellen E Jones

Jason Watkins & Lady Jane Grey: A Tower of London Special Not only does the Bafta-winning actor Jason Watkins think he is related to the royal courtier who oversaw the beheading of Lady Jane Grey; he also reckons he is connected to Jane Austen. The historian Tracy Borman helps him get to the bottom of it all.

Teen Predator/Online Killer

Alexander McCartney, a 26-year-old Northern Irish man who used catfishing techniques to become a prolific online child abuser, was jailed for life last month. This triple bill details how he was brought to justice. It begins in 2019, with a police report from Scotland turning out to be the tip of a horrifying iceberg. Graeme Virtue

The Franchise