Crossword Genius

Whizz kid's very curious message, never opened (2-6)

Ross

I believe the answer is:

go-getter

'whizz kid's' is the definition.
(both can mean a talented person)

I don't understand how the rest of the clue works.

(Other definitions for go-getter that I've seen before include "Informally, an agressive achiever" , "Thrusting, ambitious type" , "Enterprising person" , "One who succeeds through energy and drive" , "Someone whose career progresses rapidly" .)

I've seen this clue in The Times.
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