Cryptic crossword No 1,277

Clever theming Natrix, although most recognised in retrospect rather than while solving. Some fun clues - I particularly enjoyed 13a, 2d, 4d, 12d, 21d among others. Not a spoiler to mention misspelling of 'vacuum' in clue for 20a, but a few spoilers in reply. Good to see something from you again, keep plotting!

Thanks Natrix, lots to enjoy here - and a clever theme (that I spotted some of, at least!). 10a is brilliant, with 13a and 4d making up the rest of my podium.