The Halcyon tells the story of a bustling and glamorous five star hotel at the center of London society and a world at war. The drama, set in 1940, shows London life through the prism of war and the impact it has on families, politics, relationships and work across every social strata, set to a soundtrack of the music of the era. The Halcyon reveals how war permeates everyone’s lives from the glamorous guests to its loyal, hard-working staff watched from within by American journalist Joe O’Hara.