A "Whitehall" success? (3)

I believe the answer is:

hit

I'm a little stuck... Click here to teach me more about this clue!

'success?' is the definition.
(hit is a kind of success)

'a whitehall' is the wordplay.
'HIT' is hidden within the letters.
However, I'm uncertain how this is indicated.

Can you help me to learn more?

(Other definitions for hit that I've seen before include "turkey? No" , "dose of illegal drug" , "Knock" , "winner" , "recording in the charts" .)

I've seen this clue in the Evening Standard.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.