Spy in disguise dropping the head on Panorama, in summary (8)

I believe the answer is:

overview

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'summary' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for overview that I've seen before include "Broad perspective formed from above, general survey" , "General summary of a subject" , "inspection" .)

I've seen this clue in the Irish Times.

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