Across:
   1. Gets Lawrence to follow River Street swiftly (9)
   8. Arguments in favour of examination by atomic groups (13)
  11. Prepared for bad dream (5)
  12. Mark is part of group that gives me a race (5)
  13. D-notices about origins (5)
  16. Ratner may be wrong (6)
  17. No sir! Get quietly back in gaol! (6)
  18. Tears shed for Daisy (5)
  19. Delicacy found in Troyes? (6)
  20. Join Tom, returning in awful hat! (6)
  21. Cardsharp gains nothing! (5)
  24. Heavenly juice from rich oranges (5)
  26. Expand part of one's mind in new circles (5)
  27. Lowering oneself to trick Mr Lynam about the finale! (13)
  28. Unable to get up plot to free Dennis (9)
Down:
   2. Chose to work on heath (5)
   3. Lets us wrestle (6)
   4. Stunned when map compiler briefly describes his job! (6)
   5. Turks Head gain victory over Saracens Head in matched pairs (5)
   6. US Electoral College provides basic education (7 6)
   7. Sympathy for lower rank? (13)
   9. Diana Cole is from Scotland (9)
  10. Keen to ditch worker (9)
  13. Begin painting on the street (5)
  14. Ten run about, return, and come in (5)
  15. Petty quarrel about river fish (5)
  22. A traveller on public transport may be an offensive person! (6)
  23. Upset with bad finish (6)
  25. Hill-top bridgehead lost! (5)
  26. Tiny goes round Director-General to get jam (5)