Across:
1 Download movie from video camera (download/remove ‘movie’ from ‘video camera’ = dcaera = ARCADE) for one’s amusement (ARCADE),
4 Official documents for drivers (LOGBOOKS) of peers (looks = L-OOKS) travelling around Oxford (-O-) and part of the UK (-GB-) (LOGBOOKS),
9 Presumably, The Boys in Blue (police) are looking for this (MOTIVE) change (move = MO-VE) around half-time (half ‘TIme’ = -TI-) (MOTIVE),
10 Those in Cairo (AFRICANS) mixed-up (= anagram indicator) in fracas (in fracas = AFRICANS),
12 Figured out (figured out = got = GO T-) how centre (‘hOw’ centre = -O), with a fair amount of (half of) luck (half of ‘LUck’ = LU-), and concert hall (National Concert Hall = -NCH) (GO TO LUNCH) take a break (GO TO LUNCH),
13 Something from the hive (DRONE) served up (= reversal indicator) in delicatessen or diner (in ‘delicatessEN OR Diner = enord = DRONE),
14 American (A) cons (fools = FOOL’S) taken to task (task = ERRAND) (A FOOL’S ERRAND) for sending the newcomer for the bubble in the spirit level (A FOOL’S ERRAND),
18 College (-C-) booze-up (session)? Off top of head (s) (‘session’ without ‘s’ = -ESSION), primarily (= position indicator) lay low (INTER-) (INTERCESSION) or the man upstairs will certainly hear about it from someone else! (INTERCESSION),
21 Challenges (DARES) some characters from fundraiser advocating (some characters from ‘fundraiSER ADvocating’ = serad) review (= reversal indicator) (serad = DARES),
22 A big risk taker (DAREDEVIL) to most of those in 21 across (most of ‘dares’ = DARE-) and 3 down (‘devil’ = -DEVIL) (DAREDEVIL),
24 Writing (from the 3Rs = -R-) to officer (Officer Commanding = -OC-) in misery (pain = P-AIN-) to take Oriental (East = -E) (PROCAINE) drug employed by those familiar with the drill building bridges? (PROCAINE local anaesthetic, especially in dentistry),
25 Named (CALLED) everyone (-ALL-) locked in by church (Church of England = CE = C-E-) key (music key -D) (CALLED),
26 An expert on spelling perhaps (SORCERER), Clare (-CE-) is consumed by awful (= anagram indicator) errors (errors = SOR-RER) (SORCERER),
27 Selfish types (TAKERS) following those going under (under) in the business world of late? (undertakers + following ‘under’ = TAKERS).
Down:
1 Unravel (= anagram indicator) anagram (anagram = ARMAGNA-)? With constant (constant = -C) (ARMAGNAC) spirit! (ARMAGNAC),
2 Honourable mention (CITATION) – is that all there is for leaders (‘Is That All There Is’ for leaders = -ITATI-) caught by scam? (con = C-ON) (CITATION),
3 Resided (lived) over (= reverse indicator) (lived = DEVIL) with underworld boss? (DEVIL),
5 Not working (OFF) – they’re (they’re) told (= homophone indicator) (‘they’re’ = ‘there’ = THE RE-) to contact firm (-CO-) with royal (-R-) director (-D) (OFF THE RECORD) in the publishing business, confidentially (OFF THE RECORD),
6 What The Masons made (BUILDINGS) of the Italian (‘the’ Italian = il = -IL-) racket (din = -DIN-) captured by wiretaps (bug = BU-GS) (BUILDINGS),
7 A rotor (a rotor) designed (= anagram indicator) (a rotor = ORATOR) for one of the speakers (ORATOR),
8 Organisation (SYSTEM) produces mass hysteria dismissing Sharia (‘mass hysteria’ dismissing ‘Sharia’ = msyste = SYSTEM),
11 Home Rule (INDEPENDENCE) for one of those in The Liberties? (liberty = INDEPENDENCE),
15 What’s more (what’s more = -AND-), head of state (head of ‘State’ = -S-) is meeting Trump (trump/outdo = -CAP-) – it’s covered by the foreign (‘the’ foreign = le = L-E) (LANDSCAPE) version of Panorama? (LANDSCAPE),
16 Broadcast (AIR) by Victor (V-) heartlessly (i) kicking partner (alive and kicking) (‘alive’ without ‘i’ = -ALVE) (AIR VALVE) on your bike (AIR VALVE),
17 Contains (INCLUDES) forged (= anagram indicator) uncle’s ID? (uncles ID = INCLUDES),
19 Puts own stamp on (ADAPTS) fresh (= anagram indicator) pasta (pasta = A-APTS) including starter of dumplings (starter of ‘Dumplings’ = -D-) (ADAPTS),
20 For the knight’s protection (ARMOUR), remove dog from guardroom (remove ‘dog’ out of ‘guardroom’ = uarrom = ARMOUR),
23 Omen from memoranda (‘omen’ from ‘memoranda’ = mrada = DRAMA) relates to crisis (DRAMA).