Factual error: When Miss Charlesworth asks where everybody has gone and Letitia answers, you can get a good view of her desk, sporting above it amongst many photos also an illustration surely out of place in 1928: the "We can do it!" girl created by J. Howard Miller in 1942 and more or less apocryphally identified with Rosie the Riveter, a feminist icon that is quite specific to WW2. (00:22:10)
Continuity mistake: Miss Fisher as 'Fern' is posing as the magician's assistant. He does the (supposedly, before the man in the crowd calls out 20 as grand finale) last throw successfully and walks up to her to retrieve the knives. They are obviously positioned differently between shots. (00:30:30)
Continuity mistake: Early on, Miss Fisher and Doctor McMillan are strolling among the dockers in the background. But Miss Fisher hasn't disembarked the ship yet, that happens in the following scene. (00:01:45)
Continuity mistake: When Miss Fisher as Cleopatra loosens Jack's tie, what remains of the knot is different in the separate shots. (00:38:25)
Continuity mistake: When Derek's uncle arrives during his interrogation, the badge and pen in front of Jack change position entirely. When the original camera angle is used again, the objects are exactly where they first appeared. (00:28:05 - 00:29:20)
Continuity mistake: As the police arrives on the crime scene, the body is lying with both arms spread on the floor. When Jack kneels by it for the examination, the dead man has one hand to his chest. (00:05:35)
Answer: Louisa's watch was broken during the struggle to get away from her attacker.
Bishop73