SOLUTION TO PUZZLE No. 8688:

ACROSS: 1 Out of one's mind; 8 Cockles; 9 Serpent; 11 Mangle; 13 Flotilla; 15 Layer; 16 Ladders; 18 Shannon; 19 Staff; 21 Alighted; 23 Bertha; 25 Signora; 26 Intense; 28 Measured tread.

DOWN: 2 Uncanny; 3 Owl; 4 Oast; 5 Easily done; 6 Marat; 7 Needles; 8 Complete ass; 10 Tears of rage; 12 Lorna; 14 Blonde hair; 17 Elsie; 18 Shingle; 20 Antenna; 22 Hoops; 24 Lied; 27 Tar.