The trouble with a series as it gets older is it can feel like a tradition, and tradition is the enemy of suspense, and it's the enemy of comedy. It's the enemy of everything, really. So you have to shake it up.

Sherlock Holmes can be wise and funny. He wasn't, at the beginning. But later on, he's got a bantering relationship with loads of people. He's got a wisdom that he didn't have in the early stage. But he stays on the mountain top, and he will die up there. He's not going to change that.

The trouble with a series as it gets older is it can feel like a tradition, and tradition is the enemy of suspense, and it's the enemy of comedy. It's the enemy of everything, really. So you have to shake it up.

You should always waste time when you don't have any. Time is not the boss of you. Rule 408.

We have a plan to top it. And I do think our plan is devastating. We’ve practically reduced our cast to tears telling them the plan … we’re probably more excited that we’ve ever been about Sherlock.

You can be as beautiful and charming as you'd like, but if you're not terrific at acting, it will mean nothing on the screen.

If you don't expect to like someone and then you do, that's an incredibly exciting moment.