Ghost Light, Part 1 showed that after years of production turmoil and confusion as to the future of the show Doctor Who could still deliver episodes featuring good writing, good performances and an element of class. This makes it all the more disappointing that this was the final season of the show before it got cancelled.
Ghost Light reminds me of the 2005 episode The Unquiet Dead with its Victorian setting and ghostly subject matter. It even matches that story in terms of quality. The chemistry between Sylvester McCoy and Sophie Aldred as The Doctor and Ace is at a peak here, thanks mainly to the script's fleshing out of Ace's past as a troubled teenager.
Due to a variety of characters, a mysterious setting and perfect execution in performance and direction, Ghost Light Part One is a perfect start to this three part adventure.