Sullivan's call was really bugging Billy. He ought to sleep on it. Yet as he got into bed Billy continued to have the same thought, suppose it was a trap. In the comfort of his bed he thought it over. In theory anyone could have picked up the phone. Was it a real cop calling. If it was a cop, could it be the mole. Was Dignum really absent. Dignum would never have told him to come in. The more Billy thought about it, the less convincing Sullivan's line became; the SIU had invested a lot in Billy, as Dignum would have pointed out. It made Sullivans judgement look amateurish. The best lie is one that is concealed within a truth. Billy realised that there was only one person who could deal with this, Dignum. But Billy had no way to contact him. This situation had never been considered, and was forbidden. Still, that had not stopped him finding Queenan when he had learned about the FBI being compromised, or worse, and needed to pass on his information ASAP.