Emsone's Castle was a comic story from the Doctor Who Annual 1979 featuring the fourth Doctor and Leela. The Doctor rather unexpectedly travels to the uncharted planet of Zorka in search of a rare mountain weed with medicinal capabilities (why? Well, he is a Doctor, right?) but ends up opposing the 'mystic' Emsone, who for reasons best known to himself is turning innocent people's clothing invisible (yay!) and their flesh with it (urgh!) with his 'M-Ray'. Predictably, it's all part of an elaborate trap to snag the Doctor himself and put his Time Lord brain to work for Emsone himself, but luckily the Doctor makes his castle collapse on top of him. So that's alright, then. The art seems to be by Paul Crompton.
Later, Brian Bolland apparently redrew the strip, or part of it, as a sample when he was being considered for the newly conceived Doctor Who Weekly.