Yesterday Across:

1. Antagonism 7. Inter 8. Madness 10. Scrutiny 11. Stir 13. Cousin 15. Serene 17. Abet 18. Soft spot 21. Sterile 22. Alien 23. Assessment.

Down: 1. Alter 2. Turn tail 3. Gaming 4. Nude 5. Spectre 6. First-class 9. Serpentine 12. Heatwave 14. Useless 16. Lowers 19. Point 20. Dive.