Mark admits that just over a year ago not only was he blissfully ignorant about the environment, but irritated by all the talk about it.
While he didn't actively pollute, drive a huge car or honk the horn at passing wildlife, he had certainly never done anything eco-friendly.
Then he saw the error of his ways.
Mark has calculated his carbon footprint and is horrified.
He decides to admit his shortcomings and set up an organisation to attract similarly incompetent but willing people to join him in taking the first halting steps to improve their act.
Mark continues his battle whilst on a comedy tour of Australia, with mixed success.
Mark is bemused to discover that his personal crusade has led to his being regarded as some sort of expert.
He decides to get his head round some of the facts.
Mark does his first comedy gig on the subject of the environment at the Big Switch Off in Melbourne.
But in spite of his efforts, he is still struggling with his battle.