Complete
00:00:00
8 10 13 16 6 5 19 1 17 2 9 14 3 11 15 4 12 18 7
  1. 5 a Heights above sea level (9)
  2. 8 a Essence (sometimes hard) (4)
  3. 9 a Person from whom one is descended — no traces (anag) (8)
  4. 10 a Jagged (6)
  5. 11 a Sheen (6)
  6. 13 a Teeth straighteners (6)
  7. 15 a Binding agent (6)
  8. 16 a Ambiguity providing a way of avoiding a legal obligation (8)
  9. 18 a Bird of peace (4)
  10. 19 a Place to live (9)
  11. 1 d Likely to react badly? (8)
  12. 2 d Numbering system using only 1 and 0 (6)
  13. 3 d Part of a car wheel (6)
  14. 4 d FBI agents (4)
  15. 6 d Where company directors get round the table (9)
  16. 7 d The Girl from Ipanema's dance? (5,4)
  17. 12 d Weak and ineffectual person (4,4)
  18. 14 d Unemotional (6)
  19. 15 d Ingenious (6)
  20. 17 d That was a narrow thing! (4)

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