Across:
   1. see 27
   5. Where you'll find "Octopus's Garden" fantasy based on taking drug (6)
   9. Man due Order, conquering both poles (8)
  10. Facility where public finally get new anime? (6)
  12. Popular choice of angular variable that changed over time (eventually) (5)
  13. Parts used on boats and cars look different (8)
  15. Get back from unfortunate "miracle" (7)
  17. Mean old greeting, with anger (7)
  18. Big Bird somewhat bemusing (3)
  19. What has many layers, with an irrational core? We might not agree on this! (7)
  21. "Recooked" Italian cheese of type tracing ancient roots (7)
  23. Cloth maker wrapping king with bright top which exhibits the usual forms (4 4)
  24. Method by which tantrum turned into a regular theme (5)
  27,1ac. With small measure of energy, French wine kept chilled (without French refrigerator) for president (6 8)
  28. It may create an impression, and create confusion around news (8)
  29. Marge and I getting entangled was just an illusion (6)
  30. Rare artefact: spacey music genre in mono? (8)
Down:
   1. After tea, pace bowler Lee returned... a muscly beast who has a lot to say (10)
   2. Love getting weird about union and immature egg (5)
   3. State country not available (7)
   4. American Dad's visitor returned to interrupt FBI chaps, and led back key scientist (6 6)
   6. Does pie crumble in this instance? (7)
   7. Bask after amazing meal (9)
   8. see 22
  11. "Use trial guru robe"... Hindi for "all get stripped for the old guru" (3 9)
  14. Confuse cook heartlessly about English actor (3 7)
  16. Con artist who markets "life force"? (9)
  20. Vague idea of product of octopus and fish (7)
  22,8. Model craze on maid fixation (7 4)
  25. Got an unusual form of exercise? (5)
  26. Computers set up for fraudulent enterprise (4)