2551: Madness
From our UK edition
Unclued lights (including two of two words) suggest nine words (all in Chambers) starting with the same four-letter word that will appear diagonally in the completed grid and must be shaded. Across 1 A grass posing as gulfweed (8) 5 Dip in swirling river (3) 13 Oxford college with pool and some land (7)