Mo was the nightwatchman for a drilling project run by Dr Nasreen Chaudhry and his father-in-law in Cwmtaff, Wales. He was taken underground by the Silurians and was strapped to a surgical operating table and partially vivisected by Malohkeh, a process that left a large scar on his chest. (TV: The Hungry Earth) His son was also taken by Malohkeh and put in a stasis chamber, while his wife was left on the surface.
With the help of Amy Pond, who was also taken and nearly vivisected, he escaped the Silurian laboratory and attempted to rescue the Eleventh Doctor and Nasreen who had been taken hostage by Restac. They were taken prisoner again after the failed rescue, but later released by Eldane, after which he was reunited with his son. On the surface, his wife killed Restac's sister the warrior Alaya, which prompted a military insurrection on her descent to the Silurian city with the body. They were pursued, but with the help of Eldane, managed to flee in the Doctor's TARDIS, leaving Nasreen and Tony voluntarily behind. (TV: Cold Blood)