Guardian Prize Crossword (No. 29,900)

In which I attempt to solve the Guardian's Prize Crossword No. 29,900. To see real experts solve crosswords and other puzzles: Cracking the Cryptic -    / @crackingthecryptic   David Webb/Dweebovision -    / @dweebovision   For beginners, I recommend the Guardian's Quick Cryptic: https://www.theguardian.com/crossword...