S12, E11: When Rachel Harrington's bones are found in Zambia, her father's employer and mine owner Peter asks his childhood friend Nikki to fly out. Rachel had been accusing the government of a health cover up. The local police claim that Rachel was killed by wild animals. Leo and Nikki examine the bones and determine that the body received multiple stab wounds - but when they do a full post mortem, they realise that the bones belong to a woman in her mid forties, not Rachel.