Mark spent all his early crossword career as a solver, winning the Times competition a record twelve times.  He has also branched out into other puzzles, regularly reaching the final of The Times Sudoku Championship, and finally winning it in 2014, and again in 2018, the last time it was held. He has also represented the UK in the World Sudoku Championships from 2013 to 2018.

Mark was born in 1965, and has two children. As Mr Magoo, he has been setting puzzles since the turn of the century, mostly for the Magpie, has six appearances in the Listener, and was invited in 2010 to join the team compiling for the Spectator.

With Simon he started the YouTube channel Cracking The Cryptic in the summer of 2017. It quickly became clear that a worldwide audience preferred watching sudoku solving to crosswords, and the number of subscribers has passed 450,000 as of April 2022. Producing a daily video each for the channel has become both Mark’s main job.