The Great Mouse Detective1986

Dawson:
Now, wait just a moment. How the deuce did you know that I was a doctor?

Basil:
[grabs his pistol from Dawson and picks up one of bullets] A surgeon, to be exact. Just returned from military duty in Afghanistan. [blows a dust off the bullet and places it in his pistol, then closes it and looks at Dawson] Am I right?

Dawson:
Why, ha-ha, yes. [yanks his left jacket lapel to declare his name] Major David Q. Dawson. But how could you possibly--?

Basil:
Quite simple, really. [picks up Dawson's left arm to eye a stitch on his coat sleeve cuff] You've sewn your torn cuff together with a Lambert stitch, which, of course.... [puts his right arm around Dawson] ....only a surgeon uses. [then taps Dawson's right cheek gently until rushes to a couch and stacks a few colorful round pillows] And the thread is a unique form of cat-gut, easily distinguished by its peculiar.... [whispers to Olivia] ....pungency, found only in the Afghan provinces. [gets his pistol ready to be shot to the pillows]

Dawson:
Amazing!

Basil:
Actually, it's elementary, my dear Dawson.