Olympic host covered in advertisement

Across
1. Plug in the hybrid and relax (7,2)
6. Croquet, essentially? (5)
9. Characteristic of backstabber: striking the back repeatedly (5)
10. Vessels for mixing basil cereal (9)
11. He made a list of small children misbehaving (9)
12. A little timeworn ceremony, repeated so often it’s no longer interesting (5)
13. European airline has iron boxes for keeping valuables (5)
15/17. Freeloader regularly misled British writer (3,5)
18/20. Doctor Case has spoken to describe area off the coast of Queensland (5,3)
21. Sound from car radio’s back (5)
23. Competing against Vader, leading Force beyond the Dark Side (5)
24. Sickly beagle? Vet gives something to eat (9)
27. It takes one person to spread glue around oral opening after infection (9)
28. Some assassin in Japan (5)
29. Excitable flying wyvern lost its head (5)
30. Republic of Iran’s confused with Oman (3,6)

Down
1. Biblical figure works with flowers (7)
2. Visual representation of Greek aphorisms’ "top three" (5)
3. An American follows New Year’s celebration, getting serious disease (7)
4. Following the first of Lance Armstrong’s employers is nosy? (5)
5. Previous Olympic host covered in advertisement (5)
6. Mechanical lover? Finally, zero body odour and involuntary muscle movement (7)
7. Entitled to indication of learner’s permit, provided that’s inside four-wheeler (9)
8. Sad teen running to area in England’s capital (4,3)
14. Before revolt at the front, rule assumed by enemy (one from another land) (9)
15/24. Girl eats 24 across north of ancient, original location of Luxor (3,5)
16/25. Occasionally leave a 24 across for French actress (3,5)
18. Term associated with Virginia conservatives’ leader: "backward-looking troglodyte" (7)
19. Switching hands one time, like a king in a lawful manner (7)
21. Connected pair in insect heads: external appendage, a feeler organ (7)
22. Herb Anderson, initially dismissed Hollywood star, is drowning in Oscars (7)
24. (See 15 down)
25. (See 16 down)
26. Lastly: Suburb from Down Under – one near central Sydney and ocean’s coast (5)