Miss Fisher receives a confession to killing Donald with white pills from a brown bottle that were crushed and put in his whiskey. When Miss Fisher is shown the bottle of pills, it is a clear bottle, not brown.
In Cec and Bert's scene as palace guards, Cec has a line, even though this is a silent movie. Only later is it decided to dub sound on to it.
Inappropriate music accompanies black and white footage of a recorded fight between the lead actor and the film director, making a joke of their serious altercation. The frivolous music does not follow the actions or attitudes of any of the characters. It is rather a modern callous regard for early film-making.
Jack mentions that Donald was frequently late on set and kept forgetting his lines, though Raymond had already clarified to Dotty that this was a silent movie.