Absolutely stellar puzzle from Picaroon full of wit, ingenuity, and well hidden definitions.
FOI was 9a followed by 11a.
In terms of difficulty I'd say it sits towards the harder end of the scale.
If you do get stuck there is at least one long anagram in both the acrosses and downs.
My only queries are with the "under" part of 20d .... OMG! I see it now - another brilliant clue:-) so that just leaves the choice of "set" in 16a but I'm sure Picaroon had a good reason.
COD - Too many great clues to list but, if I had to pick one, (well, it is COD Bren!) it would be 10d, although clues like 20d (which I've just now understood) ran it very close.
Thanks to Picaroon for a real treat - more like this please:-)
Did you enjoy this as much as me? Leave a comment letting us know how you got on and, as always, if you do run into problems, just post your query on here - we're a friendly lot and there will always be someone on hand to help.
Stay safe:-)