On the tennis court, Nick Kyrgios has beaten the world's best – the likes of Rafael Nadal, Roger Federer and Novak Djokovic included. But the lanky sports star knows his limits. When he took on the job of sideline commentator for reality favourite Australian Ninja Warrior, he didn't even give the course a try.
It's been a long road for the 28-year-old. After impressing in the first three seasons of Australian Ninja Warrior, Jack fractured his L3 vertebra while cliff-jumping in Bali. The Indigenous "Deadly Ninja" was unable to compete in season four, but is back stronger and more focused than ever.
When Judith was 11, she asked Olympic gymnast Olivia Vivian for her autograph. Inspired, Judith gave gymnastics her all. When she narrowly missed out on selection for the 2016 Olympics, the 24-year-old switched to rock-climbing. Now, after falling in her heat last season, she's determined to make it to the finals.
Mat was inspired to have a crack after watching girlfriend Judith compete in season four. But don't underestimate the 29-year-old. With years of rock-climbing and ultramarathons under his belt, he has what it takes to conquer the most challenging of obstacles.
After Jake's first appearance in season four, the dorky rat enthusiast became a favourite. In his second time around, the 29-year-old police officer is hoping to show Australia what he's made of.
Being the first person to ever reach the top of Mount Midoriyama puts a lot of pressure on the 28-year-old to live up to his reputation – especially with new underwater challenges thrown into the mix. Can the reigning Australian Ninja Warrior champion do it all again?