All except four clues contain a superfluous word each. Initial letters of these words spell the titles of four 29D by 39 (two words). The first title defines four unclued lights; the second and third titles are defined by the remaining unclued lights. The fourth title (four words) is a cryptic indication of a sequence of letters formed by two clued lights; these must be highlighted.
 

Across

 
11    Branch of medicine perplexed our grey nurse (12)
14    Sailor in hurry risks a skin disease (7)
16    Hard, entering unknown number again (4)
17    Close game missing high tension (5)
18    Revolutionary around outset runs town (6)
22    Coins formerly distributed rest under silt (8)
23    Give power, reversing grudge (7)
24    Vase, strange in fashion, exciting thing (6, hyphened)
27    Verminous outbreak around dry island (7)
29    Task adjusting cask in a ring (8)
35    Nag unsettled one monkey (4)
37    Alien out in space in conjunction (7)
38    Stick strip, current kind (5)
40    Dispatch second deposit (4)
41    Erratic nuts troubled skilful master (8)
 

Down

 
1    Northern instructor after season dropping weak trainee (6)
2    E.g. Trotsky revealed? Not right time (4)
3    Attorney in court I carelessly nettle (6)
4    Soak grain in smooth separator (7)
5    Surpassing in striking appeal, earn money in tough broadcast (10)
6    Competitor forward in charge (7)
7    Restoring balance, I coach variable team (11)
8    Soldiers in outfit ate snake (5)
9    Sugar rings in nest box? (9)
10    Cheers regular guy, drink raised (6)
13    Leftovers end most messily around deserted office (8)
15    Companion in illness tries changing hospitals (11)
19    Capital information about gold, we note, got garbled (10)
20    Lotion provided tan, covering little up (8)
21    Following alert, hounds ran wildly, not identical (9)
26    Duplicated poem dictionary excluded (7)
28    When embedding new line discard old plants lacking pigment (7)
30    Energy in imitation pleased a baboon (6)
31    Plan upset good editor, failing (6)
32    Knowing about holy Italian well (5)
36    Pulse in bad time halved (4)
 
A first prize of £30 for the first correct solution opened on 21 October. There are two runners-up prizes of £20 (or, for UK solvers, the latest edition of The Chambers Dictionary — ring the word ‘Dictionary’). Entries to: Crossword 2133, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.