Suspect X was caught on CCTV at Purley buying a Zone 1-6 Travelcard. He caught a train to Tattenham Corner but didn't exit the station, or indeed the train. They were next observed at London Bridge, writing some figures down in a book. Later, CCTV caught them at the end of platform 10A at Stratford; a platform that sees little (if any) passenger traffic. Again they appeared to be writing something in a notebook. The suspect was at that location for almost two hours and was seen fumbling with something in their bag on a number of occasions. The suspect then appeared to travel via a rather convoluted route, next being seen at South Kenton. Again, there is no evidence that they left the station. Finally, the suspect was noticed, by many CCTV cameras, to be loitering at Paddington, walking from one platform to another without any apparent attempt at catching a train.