Cryptic crossword No 2,793

Across

1. Careless riders do perturb (8)
2. Filthy house, beyond the bounds of decency (5)
3. Cheeky clue? Balderdash! (8)
4. In Boston, dance for money (4)
5. Leading fast when bishop is traded for pawn (6)
6. Run away from pet seal (4)
7. Humble bachelor bathed in river (7)
8. Judge sees early sign of embezzler's backsliding (6)
9. Hollow, low-down scoundrel finally captured (4)
10. John thanks tenor and alto for short oratorio (7)
11. Sat back, surrounded by countryside - so peaceful! (5)
12. Staff chef cribs recipe (5)
13. Sally, naked, disported freely (7)
14. Quiet piano passage's beginning after a rest (7)
15. Craving unlimited prestige (4)
16. On edge, being trapped in deserted theatre (5)
17. Fringe elements of popular awakening unsettle European capital (6)
18. A secretive sort, nervous man leaves bustling monastery (6)

Down

1. Pronounced cardinal rule (9)
2. Blame leaders in Tehran, Havana and North Korea (5)
3. Become agitated when cheetah finally escapes gorge (7)
4. Champion leading in game (7)
5. Sample a portion of ragout (a stew) (5)
6. Remote path with river flowing to the south (5)
7. Damaged orange blossom? No loss, it'll come back (9)
8. Hope musical, short of a year, shows staying power (9)
9. Fold sheet, moving end to middle (5)
10. A trip's ending - coming back, deep sleep is just the ticket (7)
11. Spanish champion engaged in heroic exploit, following one in French Open (9)
12. Top Gear cast in kitchen garden (7)
13. Without end to quiet sleep phase, see terribly (9)