McEwan creates well the atmosphere of a post-war, pre-wall Berlin, amplifying our imaginings. The interaction between Brits and Americans is full of subtle humor, and as it later turns out, great regard and humane understanding. The narrative is smooth and concerns an everyman, virgin, British geek assigned to an American intelligence project consisting of building a tunnel crossing the border into the Russian zone to tap underground phone cables through which presumably important matters are discussed (remember, we are in 1948, almost a decade before Sputnik). Love interest and sexual education is provided by an experienced German girl to our Brit, the virgin geek. The writing is so smooth that one doesn't realize one is turning pages and reading on at a rate as if one were reading a chock-full-of-events thriller when in fact not much is really happening; the tunnel is just chugging along. But McEwan is a "smooth operator" and he is moving you along, hinting at tension, to the point you are expectant of actions or revelations in the intelligence component of the novel to pop-up any minute and throw everything topsy-turvy.
Rest assured McEwan is too smart to do that. Nothing happens as such that you are aware of for three quarters of the book until our everyman, the somewhat endearing British geek is plunged into a grand guignol not of his making and totally alien to the place where you would have expected the excitement you were owed to come from.(After all, you bought the book and it was sold to you as a thriller, and after all, it takes place in thriller-city and all major protagonists except two are freeks and geeks and goons and guards mostly in uniform and with varying levels of security clearance in the intelligence services of the powers which split this city. At times it looks as if each agent has his little black book which lists the interests they are called uypon to protect, investigate, eliminate, whatever, and thus move quickly about, talk with other similar blokes and keep moving about. The Tunnel provides a country-club of sorts for those connected with the project. There are body parts indeed, but they do not come from there.
So, much activity occurs in our atmospheric tunnel, yes. But nothing happens there really. The unwelcomed death occurs elsewhere, has nothing to do with Military Intelligence. The neatly wrapped body parts do not bring the Tunnel down, it's the disguise they wear. But the story does not end there.
Many years later a mature, no longer virginal Brit geek comes back to Berlin, post wall, to revisit sites, and carries with him a letter explaining what precipitated events at the tunnel and freed him of any trace of guilt, if any such he held.
The explication at the end of the book is clear, surprising, and truly closes the nattarive in an intelligent, satisfying way.
Endearing Love, after such an unforgettable opening and the obsessive development remains my favourite McEwan novel so far. Saturday is contrived, feels Thatcherite and stacked against the lower orders. Nonetheless I appreciated the medical tracts. (It's up for a Booker). In short, I liked "The Innocent" Better.