I assumed the symmetrical shape was meant to represent a shoe. Tangentially, if you’ve ever read the biography of Otto Kretschmer, the WW II U-boat ace, you’ll believe it should be the other way up
I'm a bit slower than the rest of you today. Hints on 17d please "Something to chew over, $100 in previous taxes" (9) with an extra letter in the wordplay. I have SU-C--S--.
Thanks Buddy, that's cleared up the bottom half. A hint for
12a, "Tenants start to seek backing in the absence of opposition" (6) should help me finish the top, although I'm lacking a lot of extra letters from the acrosses.
Thanks Xwordfan, I'd just got there by guesswork but that explains it nicely.
I've found all the theme words but frustratingly have one blank cell left. For 3d I have CAM-E, and nothing seems to fit. Have I got something wrong?