Joan: You heard what [Gregson] said.
Sherlock: I did. He doesn't want us to get killed. But I feel the same way about him.

Felipe: And how did you come by such information?
Sherlock: I used to buy heroin from him.

Joan: Wow. You're really good at this [making models].
Sherlock: You sound surprised.

Joan: What is that mush?
Sherlock: Mush. Or more accurately English porridge, made from an 18th-century recipe.
Joan: Well, it certainly smells like it's 400 years old.

Joan: How do you feel about it?
Mary: I'm proud, proud to have a daughter who cares enough about me to have this hard conversation.

The killer was performing a ritual, the ritual of obfuscation.

Sherlock [to Marcus]

Gregson: This is our first occult killing.
Sherlock: This is my 20th.

Sherlock: Would you agree I'm an excellent judge of character?
Gregson: Sure.

Sherlock: [Other detectives in the 11th Precinct] are definitely excellent people. It's just ...
Gregson: It's just you annoy a lot of people.

Sherlock: I don't know how much you paid for your toupee, but it was worth it.
Vucelich: Thank you.

I love what you did for Marcus, getting him in with the Marshals. But he's going to be difficult to replace.

Gregson [to Sherlock]

Sherlock: You don't wear a watch.
Marcus: You really are a master of observation.

Elementary Quotes

Holmes: Why do you suppose you hate your job so much?
Watson: I don't hate my job.
Holmes: You have two alarm clocks. No one with two alarm clocks loves their job. Two alarm clocks mean it's a chore for you to get up in the morning.

Watson: How do you do it, guess things?
Sherlock: I observe and then I deduce.
Watson: How did you know I was a doctor, you said you could tell from my hands.
Sherlock: Hand, singular. It was soft no calluses.
Watson: How did you know my father had an affair?
Sherlock: Google. Not everything is deducible.