The Ghastly Ones

Three sisters, Veronica, Victoria, and Elizabeth, receive letters from their late father's lawyer informing them that their father wishes they spend three nights in his house on an isolated island before his will can be read. However, a deformed hunchback named Colin leads them to the eerie estate where depraved horrors await. As the sisters face brutal murder one by one, the true identity of Ruth - Hattie, the eldest sister seeking inheritance - is slowly revealed in this 1968 American horror film directed by Andy Milligan.