Blake tells Mortimer that Olrik's presence was reported on American soil and that he came to assist the FBI since he knows the renegade best. Discretion meant that he had to keep this from Mortimer, a common occurrence in their relationship. Mortimer tells the Feds of his adventure and Calloway decides to use the element of surprise and attack the pumping station before the invasion plan can get underway. An attack is launched but the station is found empty. Evidence left behind shows signs of a sudden departure which means that Olrik and Z'ong are about to carry out their plan, which was dubbed Operation Poplar Trees, a word included on Macquarrie's baldric.