A concert is being organised at Downton to boost the morale of the soldiers, who themselves are to take part. Edith is the chief organiser and finally agrees to get Mary to help with some singing. Cora and Isobel have a huge argument over the running of Downton. Isobel feels she is being pushed out and Cora, she believes, just wants to show off and play the lady of the manor.
Their disagreements escalate until Isobel, in a furious rage, declares that she is going to leave Downton and join the Red Cross in France, where she believes she will be of more service. When she leaves, Mrs. Bird and Mr. Molesley find themselves with nothing to do and so, after one soldier comes to Crawley House looking for food, they decide to operate a once-a-week soup kitchen to feed those who have returned from active service. When they are found out by Mrs. Patmore and Daisy, the two women help out by bringing food from the Downton kitchens which is left over from army rations after the officers recuperating there have been fed. Miss O' Brien catches them in the act and reports the incident to Cora. She goes with O'Brien to Crawley House and surprises everyone by stepping in and helping herself and making O'Brien do the same.
Lord Grantham is devastated to learn that Matthew is missing in action and they all pray that both he and William are alive somewhere. Mary is suffering most particularly but she tries not to show it. His Lordship tries to talk her out of any alliance with Sir Richard Carlisle but it seems that her mind is made up. His Lordship also talks to Bates and persuades him to return to Downton as his valet, which is a disappointment for Molesley as he was hoping to secure the job. Bates is convinced that his estranged wife, Vera, will leave him alone and not cause any scandal as long as he gives her enough money from his late mother's estate.
Branson declares his love for Sybil and she is shocked, as is Mary when she questions Sybil later on the subject and Sybil is very defensive. Branson is determined that Sybil will marry him but Sybil herself really doesn't seem quite so sure.
The night of the concert arrives and all is going well. Mary is in the middle of her song when Matthew and William walk in safe and sound and Matthew joins her to sing the final bars while Edith plays the piano. It is clear that the two are still very much in love, a fact commented on by Her Ladyship but this does not make the fact that he is engaged to Miss Swire any less of a reality.
Mrs. Hughes has to dismiss Ethel Parks when she sees her being intimate with Major Bryant but gets the shock of her life when she Ethel returns and announces to her that she is pregnant by the Major.