"Monster Maker" is a 1989 45-minute television special, adapted by Matthew Jacobs from the 1979 novel of the same name by Nicholas Fisk .
When Matt learns that his hero's studio is in his hometown, he visits and shows the staff his creations.
Even the taciturn, surly Chauncey is impressed by Matt's work, and agrees to hire him as an assistant.
Chauncey begins to mentor Matt in the art of monster making, showing him a giant, dragon-like puppet they're currently building called "The Ultragorgon."
Ultragorgon operated by Martin Anthony, Tony Ashton, Michael Bayliss, Marcus Clarke, Sue Dacre, David Greenaway, Brian Henson, and Christopher Leith.