Devastating news from the front rocks the very foundations of Downton Abbey, and it's up to the Dowager Countess to buck bureaucratic protocol and bring Downton's men home. Meanwhile, the other Bates is back! Vera's return threatens to unite a questionable couple...and destroy a happy one.
Sybil confides in Mary about Branson, O'Brien sets her sights on new and returning targets, Thomas exerts his new authority, and Ethel discovers an age-old way to support the war effort. But then disturbing news arrives from the front.
Lavinia's secret surfaces, Anna has a glimmer of hope, and the domestic war heats up! Now a convalescent home, Downton Abbey provides comfort for the wounded, and drama for its inhabitants.
Two years into World War I, Downton Abbey is in turmoil, as Matthew and other young men go to war -- or avoid it. At the war front, life intensifies for Downton's young men in the face of untold horrors. Far from the trenches, there remains no shortage of scheming, meddling, and dangerous attractions.