In the novel Evil Under the Sun, Alice Corrigan was a young woman who was found murdered some time before the events on Smugglers' Island. Her body had been found by a woman hiker Christine Deverill in Caesar's Grove on Blackridge Heath in Surrey. The hiker ran to Bagshot to report her discovery. Suspicion at first centred on her husband Edward Corrigan, partly because he was a "mystery man" and little was known about his background. Alice had married him against the wishes of her family. She had some money of her own and had insured her life in favour of her husband. However her husband had a solid alibi.
The unresolved case of Alice Corrigan came to light when Poirot asked Inspector Colgate to draw up a lot of unsolved cases of strangulation in the past three years. Together with her case was that of Nellie Parsons who had been murdered less than ten miles away. Looking at both cases and correcting then with strangulation of Arlena Marshall on Smugglers' Island, Colonel Weston and Inspector Colgate both thought they saw a pattern which pointed to someone linked to Surrey.