Two unclued lights form the title by which a 38 32 is commonly known. This title’s first word defines one unclued light, and can also be divided into two words, each of which is defined by an unclued light. The title’s second word defines each of the remaining three unclued lights. Ignore one diacritic in an unclued light and one in a clued light.
 

 Across

 
10     Component of tracer, late model designed to follow dog (12, two words)
11     Joyful cry about part of Bible with right opening (5)
13     Old medicine, poor, mixed with illicit drug (7)
14     Indulged eagerness, releasing our firework (6)
16     Amphibian near plug (4)
21     Mist spreads cloaks in Scotland (8)
23     Tendency mostly to break even? It’s a gift (7)
25     Mountain in surreal picture (3)
26     Goblin wrong to return (3)
28     Checks stone in westward range (7)
29     Busy once daft rule changed (8)
34     Crustacean is able to run around inside package (8)
35     Sticky substance in tree (4)
36     Revolutionary agent gathered composure (6)
39     Alien after power in helmet (5)
40     Fish reproduced in art, each having two gills (12)
41     Refuse for example to interrupt service (6)
42     Impressions from Washington area as received by courts (8)
 

Down

 
1     Bob, say, lacking energy, on screen least (9)
2     Old bears are in existence (4)
3     Rodent showing hesitation in swimming big lake (6)
4     Whiteness originally in layer in ring, not hot (6)
5     Member of gang carrying crate newly filled with honey (8)
7     Outlets for tunes (5)
8     Cracked cup lately filled with old disinfectant (10)
9     Thin? Correct, short of mass (5)
12     Devout person upset about possessions lost in guesthouses (8)
15     Tedious prohibitionist grabbing attention (6)
18     Strange part in story captured by great religious artwork (10)
22     Strait stopping vessels going north in groups of six (9)
27     Assesses fears involved with intake of iron (7)
30     Odd pieces from forger sick of painting (6)
33     Server, not weak, set up for networks (5)
37     Still time for Scottish entry (4)

A first prize of £30 for the first correct solution opened on 19 June. There are two runners-up prizes of £20. (UK solvers can choose to receive the latest edition of the Chambers dictionary instead of cash — ring the word ‘dictionary’.) Entries to: Crossword 2312, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.