Teacher Sarah from Hertfordshire dreams of climbing Mount Kilimanjaro but first she must take on the mighty Cube; while pizza delivery man Tony reckons he's got what it takes to beat it - but can he deliver a performance good enough to win a quarter of a million pounds?

Backed by his family, 64-year-old Fred takes a no-nonsense approach to the Cube. While personal trainer Annette hopes she can stay calm under pressure and take home a cool quarter of a million pounds.