Natalia Gastiain Tena is an English actress and musician. She played Nymphadora Tonks in the Harry Potter film series, and the wildling Osha in the HBO series Game of Thrones.
A boastful girl at a Halloween party tells Mrs. Oliver that she once witnessed a murder; the same girl later drowns in an apple-fishing bucket, and Poirot must solve a two-pronged mystery: who killed the girl and what, if anything, did he witness?
