Take the plunge with shrimps, starfish and tawny nurse sharks. Plus, a mysterious, gambling-themed “quiz event” with Bradley Walsh. Here’s what to watch this evening
8pm, BBC One
Life is every bit as strange and beautiful at the bottom of the ocean as it is on land – and it is even more profuse. In his 101st year, David Attenborough is still finding amazing things to show us. The quality of footage the BBC Natural History Unit now records is truly startling. The return of this beloved series begins in tropical seas where constant sunlight stimulates an extraordinary range of life. Look out for the remarkable team-hunting strategies of the tawny nurse sharks, as well as an incredible tussle between a pair of shrimps and a starfish that culminates in the shrimp stealing and eating the starfish’s arm (don’t worry, it grows back). Consistently amazing. Phil Harrison