I’d love to say it was Mum’s voice which rallied me on. But it wasn’t. It wasn’t even Miley Cyrus’. It was mine.

Growing up, Theo and Nancy had it all at their feet – the next generation of a Derbyshire climbing dynasty, with a mother who was somewhat of a legend in the mountaineering world. Until one day, their mother doesn’t make it home from an expedition.

The two siblings are left to pick up the pieces of a broken world. And as their life begins to take shape, they are faced with a decision: do they follow in their mum’s footsteps, risking...