Across:
1 Contract workers perhaps (HIT MEN) employed to write the Christmas No 1s presumably (HIT MEN),
4 Helix (spiral = SPIRA-L-) accommodates 100 (-C-) at first ever (first ‘Ever’ = -E) (SPIRACLE) opening of The Whale (breathing hole/blowhole = SPIRACLE),
9 Rump steak put out (‘rump steak’ put out/ without ‘put’ = rmseak = MAKERS) by producers (MAKERS),
10 Leaving parties (SEND-OFFS) offends (offends) organisation (= anagram indicator) (offends = SEND-OFF) and some at the top (‘Some’ at the top = -S) (SEND-OFFS)
12 Agrees to (SANCTIONS) produce act in (act in) play (= anagram indicator) (act in = -ANCTI-) dividing family members (sons = S-ONS) (SANCTIONS),
13 Scrape off receptacles (‘scrape’ off ‘receptacles’ = ectle = ELECT) and put in office (ELECT),
14 Pauses doing a job (COFFEE BREAKS) for firm (CO-) ahead of floatation (ahead of ‘Flotation’ = -F-) for payment (-FEE) and falls to pieces (BREAKS) (COFFEE BREAKS),
18 A fair amount of (half of) 14 across (half of ‘coffee breaks’ = COFFEE) and 9 across (‘makers’ = MAKERS) (COFFEE MAKERS) produced by baristas (COFFEE MAKERS),
21 French street (French ‘street’ = RU-E) contains gym (-PE-) (RUPEE) – the Indians get their money’s worth out of it (RUPEE),
22 Clueless (LOST) with 23 down (‘cause’ = CAUSE)? (LOST CAUSE) Presumably, St Jude wouldn’t find this challenging! (LOST CAUSE),
24 Brought to life (ANIMATED) by Edward (-TED) Fox, for example (animal), from the start (= position indicator), and not finished (l) (‘animal’ without ‘l’ = ANIMA-) (ANIMATED),
25 State (KUWAIT) of the neighbours (UK = KU-) backing (= reverse indicator) Remain (-WAIT) (KUWAIT),
26 My group (-US-) gets to park (-P-) in sight (sight = sense = S-ENSE) (SUSPENSE) of thriller writer’s creation (SUSPENSE),
27 The Count (CENSUS) wants to know if you still believe in God? (CENSUS).
Down:
1 Nostalgic in a way (HOMESICK) for tired partner (-SICK and tired) behind (= position indicator) web page (HOME- web page) (HOMESICK),
2 What happened to subject of mimicry? (TAKEN OFF) Removed! (TAKEN OFF),
3 Blame oneself (regret) for losing the head (r) (‘regret’ losing ‘r’ = EGRET) with flighty type (EGRET / heron),
5 Squeeze the juice, for example (PRESS), and put on the market (RELEASE) (PRESS RELEASE) – the journalists will certainly consume it (PRESS RELEASE),
6 One of Daisy’s relatives (RUDBECKIA) is impolite (rude) missing the final (‘rude’ without ‘e’ = RUD-) half of Beckett’s (half of ‘BECKetts’ = -BECK-) first-class (AI) review (= reversal indicator) (AI = -IA) (RUDBECKIA),
7 Opens 18 across (opens ‘coffee makers’ = COFFEE) to drink (COFFEE),
8 Stargazer loses rag (‘stargazer’ loses ‘rag’ = stazer = ERSATZ), as it’s not as good as the real thing (not real/genuine = ERSATZ),
11 This is open to debate (DOUBTFUL-) on four points, one of them repeated (four compass points = North East South South = -NESS) (DOUBTFULNESS) leading to suspicion (DOUBTFULNESS),
15 No longer blame (EXONERATE) former (EX-) criminal (con) dropping note (c) (‘con’ without ‘c’ = -ON-) to English (-E-) judge (-RATE) (EXONERATE),
16 Surreal (surreal) novel (= anagram indicator) (surreal = RE-ULARS) about one thousand (grand = -G-) (REGULARS) frequent visitors to The Bar (REGULARS)
17 Harmful material (ASBESTOS) in Belgium (-BE-) found on street (-ST-) starting off (starting ‘Off’ = -O-) and pocketed by fool (ass = AS-S) (ASBESTOS),
19 Divides (BREAKS) those at the end of 14 across (end of ‘coffee breaks’ = BREAKS),
20 No need for deceptions (no ‘need’ for ‘deceptions’ = cptios = OPTICS) in field of vision? (field of vision/science of vision or light = OPTICS),
23 Creator (CAUSE) of Genesis? (CAUSE).