‘23A/27A!’ (four words in total) is a command in ODQ (minus one word) written by one gifted 12A concerning another. Unclued down lights are words linked with the latter that have obeyed the command. 36A suggests the commander’s name in English.

Across

1 Backwater started turning east into Ohio (5)

4 Patriotic piece Bill and Lambert plus Diana arranged (9)

10    Dandy joker aboard ambulance (5-5)

11    Dog twice discovers tropical bean (6)

14    Slaves possibly taste rolls (5)

15    Islamic judge put by zero port (5)

16    One not flying from Norway with two doughnuts (6)

22    Fabulous wolf lives next to English border (8)

24    One journal dissects very good Korean poetry (4)

25    Some said Leander’s vain (4)

29    Now what’s Oscar after? (8)

32    Sort of bean from Algeria seabird snarfs? Yes (6)

34    Drinks too much Bass emitted in leaks (5)

35    Ancient god of science allowing thorium (5)

37    Busy rector wearing sandal (6)

38    Shirkers delivering precious ingots (4,6)

39    Two hospitals depress sick pastors (9)

40    Australian into sensational wine (5)

Down

1 Choreographer shows aplomb integrating Hebrew measure (10)

4 Electronic tabs official gets rid of (4,3)

5 I had definite criminal named (10)

6 Tirades from girls one cuddled (6)

7 Rare set of ladies dancing and no chaps (5)

8 Wily behind bars, earl denied evidence of debts (9)

13    Severe pastor eschews harmonizing (7)

15    Close chums culling Rex rabbits (6)

17    Singular sailor in a boat bears right in the ocean (10)

18    Hecuba’s boy emerging from Troy to annoy you and me (7)

19    Like a house on fire being ruined by onset of lightning unknown (10)

20    Flickering hologram capturing soft rabbit? (9)

21    Legendary bloodhound, top dog over middle distances (6)

26    Happen to sink first in marine action (3-4)

28    Indian gums that must be chewed and swallowed by doughboys (7)

31    Aged soak is famous storyteller (6)

33    Tigger’s fostress in vibrant wraparound (5)

34    Consular agent cuts huge tuberous plants (4)

Download a printable version here.

A first prize of a £30 John Lewis voucher and two runners-up prizes of £20 vouchers for the first correct solutions opened on 23 November. Please scan or photograph entries and email them (including the crossword number in the subject field) to crosswords@spectator.co.uk, or post to: Crossword 2777, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.