Sherlock, Series 1

Taxi Driver:
Are you ready yet, Mr. Holmes? Ready to play.

Sherlock:
Play what? It's a 50-50 chance.

Taxi Driver:
You're not playing the numbers - you're playing me. Did I give you the good pill, or the bad pill. Is it a bluff, double-bluff, triple-bluff?

Sherlock:
It's still chance.

Taxi Driver:
Four people, in a row. It's not chance.

Sherlock:
It's luck.

Taxi Driver:
That's genius. I know how people think. I know how people think I think. I can see it all like a map inside my head. Everyone's so stupid. Even you. Of course - maybe God just loves me.

Sherlock:
Either way, you're wasted as a cabbie.