Rachel Riley has been temporarily replaced on Countdown by a tattooed YouTube mathematician who teaches equations in his underwear. Dr Tom Crawford, known for his Tom Rocks Maths channel on the ...

Rachel Riley’s Countdown replacement has been confirmed as the presenter steps away from the daytime game show for three weeks. The 39-year-old mathematician joined the Channel 4 show in 2009 as a ...

Mathematician Dr Tom Crawford will stand in for Rachel Riley on Channel 4’s Countdown while she takes a short break to work on another project, it has been announced. Dr Crawford is well-known for his ...

Rachel Riley is an English television presenter, and is best known for co-hosting Channel 4's daytime puzzle show, Countdown. The maths graduate also features on the show's popular comedy spin-off, 8 ...