The killer's freeze ray was in the shop, so he used his lightning gun instead.

Gregson

If the point is to test my cognitive skills, I'd much rather do so by solving a murder.
'

Sherlock [to Joan]

Lin: How are you holding up?
Joan: Honestly, I wish I felt more. I was so young when he left that I don't even really remember him.

This man was not killed by God or Zeus or Indra or any other bolt-flinging deity.

Sherlock

Hit in the pelvis by a billion volts of electricity. Ouch!

Gregson

If you like Unicorn Utopia, you're going to love Pretty Princess Party.

Joan [to Sherlock]

Imagine the indignity of being told my brain is normal.

Sherlock [to Joan]

My personality hasn't changed.

Sherlock [to Joan]

Drew Bishop: My sister has a lot of ex-boyfriends. Which one is missing?
Sherlock: Sammy Olivetti. Tall. Tattoos. Phallus to make a Clydesdale blush.

Don't pretend you haven't seen her naked. Everyone has seen her naked. But I wouldn't lead with that if I introduce you to her.

Joan [to Marcus]

My mother's ghost recently set a room on fire, so I've been doing most of my thinking elsewhere.

Sherlock [to Hawes]

Hawes: Holmes? Anything I can help with?
Sherlock: Not yet. But if an autopsy is in the offing, I should know soon enough.

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.