The Americans resurrect the "shuttle" tactic of bombing a target, flying on to a base on the other side to refuel and re-arm, and then bomb another target on the return flight. This time, however, the turn-around base is in Russia, a determined but wary ally in the war against the Nazis. The situation becomes dangerously complicated when a Russian observer plane, piloted by a highly decorated Soviet hero, is accidentally shot down by one of the American bombers on the first leg of the mission. The suspicious commander of the Russian base refuses to release the supplies Gallagher needs to make the return flight until the man responsible for the act is identified. In the meantime, the Germans have pinpointed the location of the base, and are slaughtering the 918th with waves of air attacks as it sits helplessly on the ground. The situation only becomes more muddled as Gallagher discovers the overzealous shooter was the Soviet liaison who hitched a ride with the Group. (thetvdb.com)