Didymus Holmes has 5 Adam Kay concerts.

Their music consists mainly of parody comic songs mostly dealing with medical subjects. A few of their parodies are based on the works of American comedic song writer Tom Lehrer. They have performed at the Edinburgh Fringe festival every year since 2005. Ten percent of their sales, and all proceeds from the London Underground Song are donated to Macmillan Cancer Relief. The duo have released two studio albums, Fitness to Practice and Unfit to Practise.