With another aid worker now dead, the pathologists are trying to piece together just what Rachel was up to. Dr. Andrews tells them that Rachel had been trying to trace the source of an infectious disease that she believed had been affecting many of the local villagers. She had originally believed that the disease was water-borne but all tests had proved negative and was therefore looking at other possible sources. Yet another death however strikes the local ex-pat community. With tensions rising, Nikki finds herself in jail and and Harry getting the cold shoulder from...