The Halcyon's owner Lord Hamilton holds a secret meeting that attracts the interest of American guest Joe O'Hara, while manager Richard Garland must deal with the arrival of Lady Hamilton a day earlier than expected. Starring Olivia Williams, Steven Mackintosh, Alex Jennings and Matt Ryan.

Lady Hamilton wants Freddie to use his leave from the RAF to support her with the hotel and it becomes clear she wants to make changed and that Garland is in her sights. The hotel manager insists he's not worried and that he just needs to show how indispensable he is, but Peggy and Feldman aren't so sure, while Charity meets Joe and reveals her plans for revenge, but he refuses to help her, and Emma and Betsey hit the town. Drama, starring Olivia Williams, Steven Mackintosh, Jamie Blackley and Mark Benton.

In the wake of the fall of France to the Germans, guests flood into the hotel, including one who catches Lady Hamilton's eye - the Comte de St Claire. Peggy worries about Billy's enthusiasm to sign up as soon as he turns 18, but knows there is little she can do to protect him when his mind looks like it's made up to join his father's regiment, infamously used as canon fodder. When Max faces hostility from the staff, Emma goes out on a limb to defend him - and immediately regrets it.

Joe is offered the opportunity of a lifetime, but finds himself unexpectedly torn as the moral responsibility of staying in England to tell the story of the war weighs heavily on his shoulders. Betsey's mother comes for a surprise stay, leaving Sonny unsettled and wary of the reaction she incites from Betsey, while Lucian and Lady Hamilton continue their flirtation and Emma anxiously awaits news of Freddie when she hears that a plane from Squadron 392 has gone down.

Emma is in charge of the hotel and is put to the test hosting a society wedding for Lady Hamilton's friends the Ashworths. Celina Radimsky comes to the hotel to meet Freddie, who tries to offer consolation after her husband's death. Garland goes to the East End to help Peggy with some housekeeping, but has an encounter with a figure from his past while waiting outside a shop.

Joe is curious about Emma's work for the Women's Voluntary Service, Toby is worried sick after hearing a bomb fell on a shelter in Adil's neighbourhood, and Lucian offers Lady Hamilton emotional support.

Garland asks Emma to take over running the celebrations for the 50th anniversary of the hotel, and Betsey catches the eye of a handsome man in the bar. Meanwhile MI5 officers arrive with a warrant to search the premises.

The hotel celebrates its 50 year anniversary, but Lucian struggles to keep things in order as pressure mounts and Adil attempts to corner Toby and bring him back from the edge of doing something terrible. Garland and Lady Hamilton find a cause to unite over, while Emma is still confused about the men in her life and finally comes to a decision after talking to Betsey about love during wartime. The tension between Joe and Freddie is palpable: will it spill over?