I have extended my licence even further in the case of the holiday in Norway. The two families were together, and they did have a certain amount of social contact. The story of the relaxed mushrooming with Bauhaus, and of the games that Matthias and Pierre played together in the woods, come from Guillaume's memoirs. He says he was convinced that Brandt had long since suppressed the memory of the allegations against him - probably because he simply didn't want to spoil the holiday. In the interview with Knopp, however, a rather different picture emerges. Guillaume says that Brandt was unusually silent with him in Norway, partly because they both felt constrained by the presence of their families. (Christel seems to have done most of the talking when they were all together.) It is in any case unlikely that Brandt had forgotten the allegations. Klaus Harpprecht, Brandt's speechwriter, told Knopp that Brandt had made an effort of his own before they left Bonn to get evidence against Guillaume. He had 'touchingly' left threads on his desk overnight, and carefully arranged files and pencils; 'he'd probably read about this in novels when he was a boy.' His attempts in the play to sound Guillaume out while they are in Norway by telling him about his own involvement in underground activities before the war are my purely invented equivalent to the threads and pencils (though what Brandt recalls from those years is based very closely on what he says himself in his memoirs).

I can only say that fact has subsequently outstripped any fiction of mine in sheer implausibility. Brandt's son Matthias, who is said to have played so happily in the Norwegian woods with Guillaume's son Pierre, is now an actor. A German television company has recently produced a dramatised reconstruction of the case, and Matthias has entered the story once again. Playing the part of Günter Guillaume.

Further licence with the narrative: I have made the emergence of the Ostpolitik seem rather more clear-cut than it was. Brandt had already been pursuing a policy of rapprochement with the East as Foreign Minister in the Grand Coalition. The desirability of improving relations with the Soviet Union and its allies was a matter of general agreement; the stumbling-block was the precondition for this - acceptance of the Oder-Neisse frontier and recognition of the DDR. What Brandt says on the subject in the early stages of Act One is based closely upon various speeches he made, but I'm not aware of any occasion where he articulated it as completely as he does here, or where he laid quite as much emphasis on it in a general context. In later years he saw the Ostpolitik as his life's work, and historians agree that it was the core programme and real achievement of his government. But he knew only too well how sensitive the subject was with a large proportion of the voters, and in his declaration of the new government's policy that followed the 1969 election he gave more prominence to security, continuity and internal reform ('daring more democracy' - a famous phrase said to have been contributed by Günter Grass). There are certain parallels, one might think today, with the British government's handling of entry into the European single currency.