Richard Haydn replaced Tony Hancock due to Hancock's erratic on-set behavior. Hancock reportedly also had trouble with the mock-Shakespearean dialog.
Though based on the book "By the Great Horn Spoon!" by Albert Sidney Fleischman, the plot deviates from the book in many ways.
Bryan Russell died on October 3, 2016, exactly 18 years after his costar Roddy McDowall died on October 3, 1998.