The Grand Master was a mysterious entity who wore a hood but seemed to have no head. The Writer and Spike
Dimentos created a plan to get either the Daleks, Silence or Rock Kind to capture the Second Beginner and send him to the Grand Master as in the hands of an enemy would be the safest place for the Beginner to be away from the Death.
The Writer and Spike would rescue him after 100 years, however already having Jo killed. The Writer killed both him and his servant figure. (Battle of the Beginner)