1: The smarter Holmes

As if Sherlock Holmes wasn't clever enough, he had an even more intelligent elder brother named Mycroft.

According to Holmes himself, Mycroft had superior powers of observation and deduction, but was far too lazy to have made a good detective. Mycroft (who was plump and portly, in comparison to the gaunt Sherlock) did actually appear in a few of the stories, and was said to occupy a very important position in the British Government – perhaps in the field of intelligence and espionage.

2: The perfect pipe

Sherlock's trademark curved pipe wasn't featured in either the Conan Doyle stories or the original illustrations. In fact, it owes its iconic status to a stage actor named William Gillette.

Gillette became famous for portraying the detective on stage in the early 20th Century, paving the way for future stars like Basil Rathbone and Peter Cushing. Gillette started off using a straight pipe on stage, but soon switched to a curved pipe – saying it was easier to keep clenched between his teeth while delivering his lines. Illustrators consequently began to feature the curved pipe when depicting Holmes, and the rest is history.