Piranha, by John Sayles (Novelization by Leo Callan) (NEL, 1978).
The Keep, by F. Paul Wilson (NEL, 1983). From a charity shop
Pages from Classics Illustrated: Dracula by Bram Stoker, adapted
Savage Heroes: Tales of Sorcery & Black Magic, edited by
The Avenger No. 23: The Wilder Curse, by Kenneth Robeson (Warner
The Silver Locusts, by Ray Bradbury (Corgi, 1965). From a charity