After Ling explains to Alphonse and Winry the reasoning behind Major Armstrong's abduction of Edward as well as Roy Mustang's plan for smoking out the Homunculi, he notices Lan Fan's signal flare in the distant sky and informs them that the light they see is the "signal to strike". Alphonse, considering this mission vital to discovering the identity of Maes Hughes' murderer, decides to go along, promising Winry that he will return safely and relate to her everything that happens.