TV tonight: Lauren Lyle heads to New Zealand in a stressful new thriller

The Ridge

9pm, BBC Two

Lauren Lyle, the Karen Pirie star, gets stuck in to another meaty protagonist role in this stressful psychological thriller. Mia is an anaesthetist, and also a recovering alcoholic. After an event at the hospital threatens her career, she decides at the last minute to attend her estranged sister’s wedding in New Zealand. Worse still, when she boards the plane she receives a panicked voicemail from her sibling – and arrives to find her dead, supposedly after falling from a mountain. But Mia believes this was no accident and is instantly suspicious of her nearly-brother-in-law, Ewan (Jay Ryan). She soon finds herself immersed in the small town and questioning everything. Hollie Richardson

The Iris Affair

9pm, Sky Atlantic
From the highest-ranking mafiosi to the lowliest street urchin, the entire Roman underworld is abuzz with rumours about a runaway Irishwoman with a bounty on her head. The Irishwoman in question (Niamh Algar) is, however, more concerned about what Alfie (Sacha Dhawan) is saying to the female police officer, while Cameron (Tom Hollander) awaits his moment. Ellen E Jones

Dragons’ Den

8pm, BBC One
In one of the most eye-catching pitches yet, two wrestlers – one half-naked and oiled up – literally fight it out in the den this week. Will they help persuade the Dragons to invest in Newcastle-based Simon’s pro-wrestling idea? Elsewhere, two friends introduce their safety-first flat-sharing app. HR

Taskmaster

9pm, Channel 4

Desperate times … Reece Shearsmith in Taskmaster. Photograph: Channel 4

Reece Shearsmith hawking up a piece of bread. Ania Magliano puking up blue jelly. Maisie Adam squawking like a bird. It can only be Taskmaster and its poor contestants doing desperate things to win. There’s even a spot of mallet-wielding too. HR

All Creatures Great and Small

9pm, Channel 5
“I hate it when he’s in a good mood,” says Tristan of his incorrigible brother Siegfried. “It’s like being licked by a shorthorn!” But questionable practices at a local whippet-racing track soon provide Siegfried with a serious purpose. Tristan, meanwhile, has a cathartic one-on-one chat with a parrot. JS

Brassic

10pm, Sky Max
The last ever episode of Brassic has been teased as “harrowing”. But this Halloween-themed instalment – in which Tommo (Ryan Sampson) must steal a corpse – nails the lairy comedy’s signature mix of sarcasm, swears and sentiment. Everyone getting to dress up as vampires and mummies is just a bonus. Graeme Virtue