I had infiltrated a high end swingers party in London’s King’s Cross by dressing head to toe as an invisible ninja. I recognised politicians and influencers chit-chatting in an animated fashion in the bar. It was all pretty tame stuff. Then I spotted my former best friend, A, sitting in the middle of the crowd quietly reading a paperback. She was bound to expose me as a spy, so I decided to leave and waited for a night bus. Every bus I caught seemed to take me further away from home until I ended up in Perry Barr in Birmingham in the 1970s.