TONIGHT'S TV

Ancient Invisible Cities (BBC2, regions vary)

MICHAEL SCOTT uses 3D scanning technology to reveal the historical secrets of ancient Athens and tell the story of how this remarkable city created the world's first democracy.

He begins his journey on the Acropolis, where, in the late sixth century BC the people of Athens overthrew a tyrant and set up a democracy, and investigates a mysterious, asymmetrical temple called the Erechtheion that sits in the shadow of the world-famous Parthenon. To the south of the city, he clambers through a silver mine where an army of slaves once toiled inside the labyrinth of narrow tunnels.

The Great British Bake Off: An Extra Slice (C4, 8pm)

MANY were gutted when Imelda was shown the exit in episode one of the new run.

She'd barely been given a chance to show what she was made of when judges Paul Hollywood and Prue Leith decided she'd reached the end of the floury road. However, for Gallic baker Manon, who'd never had a Wagon Wheel (one of the challenges), she proved to be magnifique enough to win Star Baker. Obviously, there's been a lot of in-tents action since then, and dissecting every crumb of baking drama is Jo Brand and her celebrity guests. This week they meet the latest baker to exit the contest, look at some of the highs and lows of episode three, and Jo reveals her favourite pictures sent in by viewers baking at home.

Gardeners' World (BBC2, regions vary)

MONTY DON makes plans for a colourful spring by planting bulbs and nectar-rich wildflowers for an early and welcome feast for insects.

Frances Tophill travels to a Birmingham allotment to meet an enthusiast who has filled his plot with dahlias, which he grows for competitions, and Nick Bailey is at Powis Castle in Wales to find out what it takes to trim their centuries-old, 14-metre-tall yew hedges. Adam Frost visits Sezincote Garden in Gloucestershire to find out about its history, and Toby Buckland takes a look at a garden in Cheshire where different sections have been designed with small gardens in mind.

Britain by Bike with Larry & George Lamb (C5, 8pm)

THE father-and-son duo visit Northern Ireland, circumnavigating Strangford Lough and trying to spot seals en route. George then explores a popular mountain-biking location, while Larry indulges in his passion for oysters, crossing the border to Carlingford to help out at an oyster factory. The pair also meet a local leprechaun hunter to chance their luck in finding the mythical creatures, before heading to Northern Ireland's oldest thatched pub, The Crosskeys in Ardnaglass, Co Antrim, where they receive a lesson in how to play the bodhran drum.

Big Brother: Live Launch (C5, 9pm)

WITH the media speculating on whether this will be the last Big Brother series, plenty of folks are wondering: has the reality show finally gone off the boil?

That remains to be seen, but just days after wrapping up the celebrity version, Emma Willis introduces the latest wave of unknown contestants about to enter the Orwellian pre-fab. And given the fact some of the recent alleged celebrities in the house were not that famous, there's a good chance some folks going in will emerge as household names by the time the latest series is over. So, as series 19 begins, and more nervous wannabe stars follow in the footsteps of recent BB queen Isabelle Warburton, there's one key question on narrator Marcus Bentley's lips. Who wins? YOU decide.

Front Row Late (BBC2, 11.05pm)

BBC Two's nocturnal arts slot has gone through many incarnations over the years, from the sublime Late Review in the 1990s, when the likes of Mark Lawson and Tom Paulin used to assess films, books and plays, to this offering.

Previous series have featured reports on the Turner Prize, Michael Fassbender and Blade Runner 2049. Following her stint as host earlier in the year, Mary Beard is back with the topical cultural debate programme. There will be more interviews, news features and performances from the world of the arts.