Mrs. Ethel Rogers was one of the slaves on the island
Mrs. Rogers was being hired as a maid.
Ethel and her husband killed their former employer.
Shes a SLAVE ON THE ISLAND
After the accusations, Mrs. Rogers faints and is given a glass of brandy when she wakes up. Unbeknownst to anyone, however, Justice Wargrave has slipped a lethal amount of chloral hydrate (COKE) into the brandy, and Mrs. Rogers dies in her sleep that night.