The hallucination sequence in "Young Sherlock Holmes" involved the menacing pursuit of the elderly Reverend Nesbitt by a stained glass knight which has jumped down from its place among the stained glass windows of a church. The initial modeling of the character fell to artistic supervisor John Lassiter who conducted research to ensure the right look for the stained glass knight.

"We were very concerned with making the character look organic like an 18th century stained glass window that had actually popped out and come to life.  We went through two or three different design phases trying to find something that worked. We even brought in Eric Christensen, who made all the stained glass windows for Skywalker Ranch, and he gave us several suggestions, incorporating what we had learned in our research.  Eric actually produced a scaled knight out of real stained glass."

FUN FACT: In a classic filmmaking workaround, known as a pickup shot (or pickup sequence) – a small, specific piece of footage was needed to fix a continuity error to clarify a scene, to bridge two actions together. In the case of Young Sherlock Holmes (1985), the editors asked me to stand in as Sherlock for a quick pickup to maintain the illusion of a continuous chase scene. They dressed me in a Sherlock outfit and had me run down a hill and around the corner to discover that the man I was chasing had vanished.