Across:
8 Undertakers asked out? (‘undertakers’ ‘asked’ out = unertr = RETURN) Presumably, this is the reply! (RETURN),
9 British (B-) champion might do this (‘reign’ = ‘rain’ = -RAIN-) on the radio (= homophone indicator) and on television (-BOX) (BRAINBOX) answering all the general knowledge questions (BRAINBOX),
10 Some populist unfortunate (some ‘populiST UNfortunate’ = stun = STUN) from Knock (knock/hit = STUN),
11 Comparative number (-RATIO-) found in Frank’s (opens = OPE-NS) (OPERATIONS) performances in the theatre (OPERATIONS),
12 Online film-maker (WEBCAM) gets work (W-) on bass (-B-) in backward (= reversal indicator) club (club = mace = -E-CAM) (WEBCAM),
14 Language (DUTCH-) from Gents (-MEN) (DUTCHMEN) produced by low, lying foreign types (DUTCHMEN from low-lying Netherlands / part of “Low Countries”),
15 What the prodigal son might do? (RETURN TO THE FOLD) in 8 across (‘return’ = RETURN) for Count (count = tot = TO T-) – that man (-HE) from 24 across? (‘fold’ = FOLD) (RETURN TO THE FOLD),
18 Up- (up) -turn (= reversal indicator) (up = PU-) is never ending (‘neveR’ ending = -R-) and on track (track/pursue = -CHASE) (PURCHASE) for those paying for it (PURCHASE),
20 Short (e) story (‘lie’ without ‘e’ = LI-) and fables (-LIES) (LILIES) popular in the nursery (LILIES),
22 US tighten a (US tighten a) negotiation (= anagram indicator) (US tighten a = NAUGHTIEST) with the most ill-mannered of individuals (NAUGHTIEST),
24 Cave in (cave in = FOLD) Ring? (enclosure/pen = FOLD),
25 Put out (RELEASED) of meadows (-LEAS-) surround by grass (reed = RE-ED) (RELEASED),
26 Commissariat dismissing Maoist (‘Commissariat’ dismissing ‘Maoist’ = cmisa = RACISM) is a sign of bigotry (RACISM).
1 Come to terms (SETTLE) with telecaster not taking care (‘telecaster’ not taking ‘care’ = telest = SETTLE),
2 Sample of Grand Cru incomparable (sample of ‘grand cRU INcomparable’ = RUIN) to Scotch (scotch/wreck = RUIN),
3 Thin on the ground (UNCOMMON) with a foreign (a = UN-) general (-COMMON) (UNCOMMON),
4 Allowed to (ABLE) get around (= reversal indicator) Mediterranean island (Elba = ABLE),
5 Abandoned (VACANT) tax (VA-T) covering means of selling beer (in a -CAN-) (VACANT),
6 A deep understanding (INSIGHTFUL) of nervous (= anagram indicator) flight in US (flight in US = INSIGHTFUL),
7 Complex network (maze) broadcasting (= homophone indicator) (‘maze’ = ‘maize’ = CORN-) feed (-MEAL) (CORNMEAL) that’s synonymous with Porridge (CORNMEAL),
13 A worshipper (CHURCHGOER) of cold (C-), rougher (rougher = -HUR-GOER) ground (= anagram indicator) around Switzerland (-CH-) (CHURCHGOER),
14 Something from the hive (DRONE) served up (= reversal indicator) in delicatessen or diner (in ‘delicatessEN OR Diner = enord = DRONE),
16 Taught (EDUCATED) by Oriental (east = E-) from old bank (-DUCAT- old gold coin) with English (-E-) director (-D) (EDUCATED),
17 Short break (HALF-TERM) for Henry (HAL-) Furlong (-F-) and Hillary (Hillary) say (= homophone indicator) (‘Hillary’ = ‘Hilary’ TERM at university) (HALF-TERM),
19 Dramatist dismisses mad (‘dramatist’ dismisses ‘mad’ = ratist = ARTIST) creative type in atelier (ARTIST),
21 Conscript (ENLIST) gets silent (silent = ENLIST) treatment (= anagram indicator),
23 Puts back together (mends), losing leader (m) (‘mends’ without ‘m’ = ENDS) with objectives (ENDS),
24 Foremost calories (foremost ‘Calories’ = -C-) in butter? (fat = FA-T) (FACT) Every scientist knows that! (FACT).