ACROSS
1. OOC inside HH = HOOCH <hard liquor>
4. <only one> SINGLETON = SING + LET ON
9. R + TEEN* + RY = REENTRY <coming back to Earth>
10. <leader of mob> KINGPIN = KIN outside (IN GP)
11. (FIGHT ADVERSARY)* = GRAVEYARD SHIFT <overnight bout>
13. <vigorous> RUDE = R U D E
14. P inside STEM + OTHER = STEPMOTHER <parent>
17. EX + H + (IRATE outside LA) = EXHILARATE <uplift>
18. (-stagehan)D IS C<horeographing> = DISC <piece in Othello>
20. <alloy> STAINLESS STEEL = *£*SALIENT*£*
23. AIS inside LION = LIAISON <meeting>
24. I + (MAY outside GER) = IMAGERY <representation>
25. <financial officer> TREASURER = TR outside REAS(-s)URE
26. <gung-ho> EAGER = ←(RE GA E)←

DOWN
1. HER + (BARD outside G) + EN = HERB GARDEN <where plants grow>
2. (A SUSPECT HAD NONE)* = OPEN-AND-SHUT CASE <Disguise? A suspect had none!>
3. <dislike> HATRED = THREAD*
4. <M for one> SPYMASTER = SP + ←MY← + ASTER
5. <microwaved> NUKED = ND outside (UK E)
6. O inside CHUNNEL* = LUNCHEON <meal>
7. ¿?rubbish tip belonging to an iceberg lettuce¿? = TIP OF THE ICEBERG <sign of worse to come>
8. NOUN, ←N = NON-U <of things objectionable to the gentry>
12. BARELY* outside RICK = BRICKLAYER <construction worker>
15. I inside PASTRIES* = PATISSIER <one employed in cooking pastries!>
16. PSI inside ELLIS = ELLIPSIS <...>
19. <run away> ESCAPE = S inside PEACE*
21. L U N A R = LUNAR <like New Year, perhaps>
23. <accidental> FLAT = L inside FAT