8. Molly Hooper
During the two series, we see her cooing and fawning, trying to catch Sherlocks eye but Molly (the wonderful Louise Brealey) is far more than a girl hopelessly lost in a crush. Initially, we see her attempts to attract attention with lipstick and clothes and trying to get Sherlock jealous (good luck with that!) But as the series progresses, she becomes a stronger character and she manages to read Sherlock better than anyone else, even John. The unrequited love slave not only counts, she is vital and ultimately (we assume) she holds the key to helping Sherlock.
7. Costumes
When Sherlock is seen in a deerstalker, it is ironic and kitsch (How do you stalk a deer with a hat?) and with that we quickly move on from the traditional costume of the master detective. In this series we have an elegantly dressed Sherlock in snappy shirts, full length overcoat and neatly tied scarf marauding around London. John also has a pretty tidy line in outfits, even managing to pull off a chunky knit sweater without looking silly. One question that remains though is how they afford such a high end wardrobe with no apparent income?