Quickly -- like lightning? (2,1,5)
I believe the answer is:
in a flash
'quickly' is the definition.
(I've seen this in another clue)
'lightning?' is the wordplay.
I cannot really see how this works, but
'lightning?' could be 'flash' (lightning is a kind of flash) and 'flash' is located in the answer.
The remaining letters 'ina' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'like' acts as a link.
Can you help me to learn more?
(Other definitions for in a flash that I've seen before include "Almost instantly" , "Instantly, straightaway" , "Where American detected electricity" , "Very quickly" , "pictures may be taken" .)