We are raiding the Audio Long Reads archives and bringing you some classic pieces from years past, with new introductions from the authors. This week, from 2015: When Ashraf Marwan fell to his death from the balcony of a London flat, he took his secrets with him. Was he working for Egypt or Israel? And did the revelation of his identity lead to his murder? By Simon Parkin. Help support our independent journalism at theguardian.com/longreadpod