ACROSS
1. (-physi)CAL IS THE NIC(-est) = CALISTHENIC <sort of exercise>
8. COSTA + R = CO-STAR <his Juliet?>
9. <very soon> IN NO TIME = I + N + NOT I + ME
10. <extent of e.g. dragonfly> WINGSPAN = SPAWNING*
11. <cute swimmer> OTTER = HOTTER - H
12. MMO outside E = MEMO <communication>
13. <suit> FIT THE BILL = FIT + THE BILL
15. <TV presenter discussing> NEWS ANCHOR = (WHEN NARCOS)*
18. <gently manoeuvre> EASE = EASEL - L
20. <perhaps poke holes> REBUT = ←TUBER←
22. (MI + Z + DA) inside SAT = SAMIZDAT <clandestine publication>
24. I inside (MOTOROLA - A) = MOTOR OIL <product that goes inside cars>
25. <pad> TABLET = LET after TAB
26. <break up> DISASSEMBLE = AS inside DISSEMBLE

DOWN
1. CHOICE outside C = CHOC-ICE <dessert>
2. <inclined to sue> LITIGIOUS = LIT + ←GI← + IOUS
3. <band> STRAP = ←PARTS←
4. (THE RAIN)* = HAIRNET <headgear>
5. NOSHER outside (ON + K) = NON-KOSHER <breaking food laws>
6. C(-l)U(-b) + TIT = CUT IT <do>
7. <unconcerned with ethics> AMORAL = ORAL after (A + M)
13. TONICS* after FUN = FUNCTIONS <get-togethers>
14. BB outside (EEL + ZEBU) = BEELZEBUB <false god>
16. (ROB outside B) after EA = EARBOB <piece of jewellery>
17. SLEUTHS* = HUSTLES <con jobs>
19. <I don't want to know> SPARE ME = (RE inside SPAM) + E
21. <children> BROOD = "BREWED"
23. MOT + TE = MOTTE "Norman castle site"