Across 7. Treacherous person is employed by plumber with his strange, different way. (5-2-3-5) 9. Herb takes some risk to see mythical serpent. (8) 10. Extremely poor old boy. Unhappy soul! (6) 11. Hobbes’ sea serpent. (9) 13. Tree with a snake... (3) 15. …and a starting price for another snake. (3) 16. Monster with serpent’s tail has tea with me and an artist. (7) 18, 20 ac. Ethiopian prince goes after swan for snakes. (6) 21. Turn sour – or boo the serpent with foot in mouth. (9) 25. Pike of oriental length caught plant. (6) 26. A secret’s shared with a viper. (8) 27. Look - check legendary G-man ere Monday, and rest uneasily with mythical Scottish serpent. (4,4,7) Down 1. Repress tide after a point. (5) 2. Scattered Maori meal inside snow vehicle. (7) 3. Famous atoll or very little at all. (6) 4. Broken bone received in raid gone awry - but courteous. (8) 5. Good overhead surface of Scottish face. (5...