The twenty words revealed in the perimeter squares and the four 10-letter words can all be paired with both BLACK AND WHITE (hence the title). First prize Patricia Gibbs, Mountsorrel, Leics Runners-up Gemma Le Marquer, Twickenham, Middlesex; Hilda Ball, Belfast
One unclued Across light can be paired with the remaining unclued ones: similarly with the unclued Down lights. Across 12 Holes in supertanker, wrecked off North Cambodia (9) 15 Turning mad — silent strip (9) 16 Sickly marine after backing old Spanish province (6) 20 Approach shot goes round deserted vehicle (7) 21 But that