Vogel has assumed the alias of Adelheid Zinsli, a Swiss reporter, to cover the Olympic Games while spying for the British. Vogel arranges to meet with her old mentor, Peter Weill, at the Berlin Olympic Stadium, but right after Weill tells her that he needs to get some information out of the country, he keels over. While the death appears to be the result of a heart attack, Vogel believes that poison was responsible. Her search for the truth, aided by an SS officer of uncertain trustworthiness, leads her to a deadly secret.