If, like me, you cannot see a manhole with- out wondering what's down there, you must read the new edition of London Under London, a subterranean guide by Richard Trench and Ellis Hillman (John Murray, £15.99). Well mapped and illustrated, it enthusiastically describes the unknown city beneath the streets, with its hundred miles of Neolithic rivers, its 1,500 miles of mostly Victorian sewers, its 82 miles of Under- ground tunnel, its 12 miles of government communication tunnels and its hundreds and thousands of miles of cables, pipes, passages, crypts and sundry holes. Did you know there are some 40 'lost' Underground stations, frozen in time? It's a hidden paradigm of London's history.
Another paradigm — this time of mid- 20th-century Britain — was the wartime Special Operations Executive (SOE), established by Churchill to 'set Europe ablaze'. Secret Agent by David Stafford (BBC Publications, £16.99) is the book of the recent television series. Part history, part individual recollection, it is as good an introduction to this thrilling and moving subject as we are likely to get. Most notice- able is the high quality of the agents, British and foreign, compared with most of those the Germans sent over here.