In 2018, Dr Challen, alongside his diving partner Dr Richard 'Harry' Harris, were invited to assist in the rescue operation of a Thai soccer team trapped Thailand's deep Tham Luang Cave, in a story that gripped the world. The pair worked 14-16 hour days making trips into the cave on a daily basis, working cooperatively to ensure the safe evacuation from the cave for everyone. Craig’s expertise and experience in diving saw him help to de-kit the boys of their diving equipment after escaping the first flooded section of the evacuation route, carry them to the next section and prepare them for the next dive. 

His unwavering and selfless bravery following the successful rescue of the trapped soccer team saw him be awarded the Star of Courage as well as the Order of Australia for “service to the international community”. This inspirational rescue operation will never be forgotten and will now be immortalised in a movie and book which promises to portray to viewers the adverse conditions and difficult decisions which were made to rescue the children. 

Since the rescue, Craig, a retired vet, has spoken out about how the Thai cave rescue had taught him about the importance of taking advantage of life's opportunities and being ready when they arise. Craig's interest in cave diving as a hobby had motivated him to sell his animal hospital and retire; freeing up the time to spend underwater and underground. He had no idea his unique set of skills would save lives. 

Alongside educating others on seizing opportunities, Craig is keen to use his title as the 2019 Australian of the Year to foster a more inclusive society.