Continuity mistake: When Steed, Mrs Peel and their travelling companion Mr Smallwood arrive at the pub, it is pitch black. However, when Smallwood leaves a few minutes later to go and visit his brother, it is fairly light again. All subsequent shots of him outside continue to be well lit, whilst in the shots looking out from the pub it is dark.
Revealing mistake: When Steed comes out from hiding behind the spiral staircase and wall, the rim of his hat touches the wall, which wobbles, revealing a fake wall. It's very noticeable, because there is a shadow cast from the staircase to the wall where you can see it moving.
Continuity mistake: The money boxes Steed is stacking at the end keep changing positions between shots. And though they're supposed to be full of half-penny coins, the ease with which he lifts and carries them makes it obvious that they're empty. (00:49:00)
Continuity mistake: Steed tosses his opponent over his shoulder during the scuffle. The man lands on his back with his right hand extended over his head. But when the shot cuts to a different angle, both his arms are instantly down at his sides instead. (00:38:25)
Continuity mistake: The clock showing London time is 12.15 when Emma is captured. Shortly after, the ticker timer goes off, it looks like almost 5 or 6 o'clock. But the ticker message is timed at 12.15. A short time later, after the escape, it shows 10.40.
Continuity mistake: When the butler shows up at Steed's apartment to kidnap Tara, they fight and her culottes are unfolded at the knee. After he has knocked her out and put the last jigsaw pieces in the puzzle, he goes to pick her up to carry her out, and her culottes have been folded up at the knees with no way for that to have happened.