know <somebody> like the back of one's hand.

[Tae-Bbong-E]

Before I looked up this idiom in Oxford dictionary, I had been very familiar with "know something like the back of one's hand".
[ https://www.google.com/search?q=know+something+like+the+back+of&rlz=1C1CAFC_en__911__911&oq=know&aqs=chrome.1.69i59l3j69i57j0i433j0i67j0l3j0i433.1715j0j15&sourceid=chrome&ie=UTF-8 ]

However, as Oxford dictionary shows "know <somebody>/something like the back of one's hand."

So do you guys use <somebody> in the idiom?
For example)
• I know Mr. Brian like the back of my hand.

 

[Charlie Bernstein]

. . . So do you guys use <somebody> in the idiom?
For example)
• I know Mr. Brian like the back of my hand.

You could use that. Most commonly, we use it when we talk about a physical location or layout:

- I know Tokyo like the back of my hand.

- That veterinarian knows canine anatomy like the back of her hand.

- My kid knows Disney World like the back of his hand.

 

[Rover_KE]

... do you guys use "somebody" in the idiom?

• I know Mr. Brian like the back of my hand.

I've never heard it used for knowing people well.

 

[jutfrank]

Me neither.

I'd only use it for geographical territory. That's how the analogy is meant to work—the back of your hand is familiar territory.

 

[probus]

- I know Tokyo like the back of my hand.

That's an unfortunate choice of example. I'd call anybody who actually said that a fibber.