ACROSS
1. <corrupt> BASTARDISE = BASE outside TARDIS
6. (-s)AFAR(-i) = AFAR <from a long way off>
9. <strip of land> ISTHMUS = IS + THUS outside M
10. (K + VERY) outside N A = KNAVERY <bad behaviour>
12. <pull a fast one> HOODWINK = (ON KID WHO)*
14. <brewery> AMSTEL = (-stre)AMS TEL(-evised)
16. <spot> MOLE <spy>
17. <epistle> EPHESIANS = EPS around HES(-s)IAN
20. (THE A) + "TRICKS" = THEATRICS <melodrama>
21. I + A G O = IAGO <villain>
23. IL after LENT = LENTIL <pulse>
25. ←POSTS← outside WEE = SWEETSOP <tropical fruit>
27. TRIGGER = OUTRIGGER without OU
28. <Satan> OLD NICK = O + (D inside CLINK*)
30. <get rid of> OUST = (-gener)OUS T(-ither)
31. (SHEEP DELAY)* = SLEEPYHEAD <one who should be counting [sheep]>

DOWN
1. <plague> BLIGHT = BLIGHT(-y)
2. <quietly> SOTTO VOCE = (VETO COOT'S)*
3+13. ⭯WARM⭯ + (RESTING outside L) = ARM WRESTLING <strength contest>
4. <lately deny> DISINHERIT = (-ban)D IS IN HER IT(-unes)
5. <wine> SAKE = S(-p)A(-r)K(-l)E(-d)
7. <nimble> FLEET <ships>
8. SOLITARY* = ROYALIST <supporting the King>
11+29. <commemoration of end of violence> ARMISTICE DAY = (A Y) after MATRICIDES*
15. <secretly penned> GHOSTWROTE = →"ROAST GOAT"←
18. <revered father> AUGUSTINE = AU GUST IN E
19. <blade> STILETTO = ST I + ((T T) inside LEO)
22. K inside SPIED = SPIKED <with concealed drugs>
24. <deals perfectly with> NAILS = SLAIN*
26. (-m)OLAR, R↔L = ORAL <exam>