Dressed to Kill

One of the scenes depicts a "General" omnibus carrying passengers on a normal route.

The movie is set post-WWII London (1946).

The London General Omnibus Company went out of service in 1933.

Watson refers to having met the King of Bohemia.

This refers not to the land of the Czechs, but to an imaginary place of the same name, created by Sir 'Arthur Conan Doyle' for the Holmes adventures.

Watson is repeatedly described as having "no ear for music".

Yet in two previous films of the series, he is seen both singing and playing the tuba.

When Sherlock goes to see the auctioneer to ascertain who purchased the music boxes, he reads the purchasers address from the log and says its on "Hampton Way" In the next scene he visits the house on Hampton Road.

He also mentions the "correct" street, Hampton Road in a subsequent scene.

The auctioneer read the address from the log to Colonel Cavanaugh (the villain) not Mr Holmes.

When Holmes & Watson visited the auctioneer, the dialogue had Holmes mentioning the (incorrect) address.

The bus has a left hand drive, American style.

All the cars and taxis have right hand drive, which is correct.

When Holmes is shown the first music box, he is allowed to hear just its first few bars.

Still, he then whistles the entire tune as if he knows it.

However it soon develops that the tune is unique, and Holmes could never have heard it before.

He could not have whistled it entirely.