You had expected this expedition to be nothing less than an archaeological miracle. For two months, you’ve all been in the Peruvian rainforest looking for the remains of the Moche people, an advanced South American civilisation that preceded the Incas and has hardly been studied.

You knew you were on the right path, as you had found countless small vases, tools and other artefacts over the past few days. Late in the afternoon, you finally found the tomb of the priestesses. This important find would have been another milestone in the career of Mary Stonerock, the UK’s youngest professor of archaeology.

Mary decided to celebrate the find with a hearty feast and an evening of drinking. You raised a toast to your joint success and speculated as to what the tomb, which was to be opened the next day, might contain. But the evening took a tragic turn when Christian discovered Mary’s corpse at around midnight in the entrance of her tent.

Director Gustavo Navarro has since notified the police using the camp’s radio. They are due to arrive at the remote excavation site in a few hours. Until they arrive, you are all on your own in solving the mystery. What happened? How could this expedition have ended so tragically?