Within Fetch Priory, Dr Fendelman had a lab where he performed experiments using a time scanner in an attempt to examine the origins of Eustace, a seemingly-human skull that pre-dated the earliest known men by millions of years.
While Adam Colby and Thea Ransome were also part of his team, it was only Maximillian Stael who was taken into Fendelman's confidence and allowed both knowledge of and participation in these experiments. The entire priory was engulfed in flames after the Fourth Doctor triggered a controlled explosion. (TV: Image of the Fendahl)
When the Eighth Doctor fell through the time fissure which Fendelman used to enhance the time scanner, he witnessed several events which occurred in the lab, including the building burning. (PROSE: The Taking of Planet 5)