Across:
   1,1dn. Big leader had them around - ran his letters a couple of times with crazy assassin (6 1 6)
   5. Senator 30, bearing expression of pain, engendered sympathy (7)
   9. Bent brow in a cheerful arch (7)
  10. I'd get 101-to-1 return being crazy (7)
  11. Big leader had them around - ran his letters a couple of times with crazy assassin (10)
  12. Denigrate men withdrawing, devoid of energy (4)
  14. Deadly Cosby character Bert killed (5)
  15. Some in Qatar come ducking back to be part of a liberal party (8)
  19. Lost more obscure musical nuances (8)
  20. Lightweight Caribbean agent  (5)
  23. A bit of prodding alright during training (4)
  25. Made sermon safe for society (10)
  27. Disaster as flying ace bled (7)
  28. Imagine Ebro flowing to the West, having been dispatched for craft coming from the East (7)
  29,30. Wicked Fred, bent Orkney politician (6 1 7)
Down:
   1. see 1ac
   2. Controls on gallery put back in place (9)
   3,7. Venue proved 14 for 29 30 with morning low pitch (love embracing sexy student) (10 5)
   4. Who might shoot boy? Crazy woman! (6)
   5. Type letters, hit enter, get number of rounds delivered to 29 30 (8)
   6. Single turn can be turned (4)
   7. see 3
   8. Nasty way to punish a group after a desertion, already badly emaciated (8)
  13. 29 30 won it as a 15, not a minion being ordered around (10)
  16. Nick consumed in pursuit of politician and scoundrel (9)
  17. Violent rides put more 10 (8)
  18. Fly back bringing rouseabout and a second person (8)
  21. Best regularly captured by rook, and captured again (6)
  22. Some loss if you stagnate (6)
  24. Carefully bake piece of bacon for dish (5)
  26. Care about vegetation (4)