The first in a series in which Jason Fox sets celebrities daring challenges designed to push boundaries and build resilience. First up is actor and comedian Rob Delaney, who is challenged to jump off a 40-metre-high abandoned viaduct. To prepare him for this, he must first dive from a cliff into a flooded quarry, and cross a 300-foot long highline spanning a 250-foot-drop.

Model Maya Jama trains with Jason Fox to bungee jump off a 75-metre-high transporter bridge in Newport. In preparation for this challenge, she abseils down a 40-metre sea cliff and rides a 100-metre zipline across a gap spanning jagged rocks.