the guests begin to suspect that u n owen is systematically murdering them. a search for owen turns up no results. the island is a "bare rock" with no hiding places, and no one could have arrived or left; thus, they conclude that one of the seven remaining persons is the killer. wargrave leads the group in determining that so far, none of them can definitively be ruled out as the murderer. the next morning, rogers is found dead while chopping wood. after breakfast, emily brent is found dead in the kitchen, where she had been left alone after complaining of feeling unwell; she had been injected with potassium cyanide via a hypodermic needle.