Liverpool, 1855. Ada Houston is alone. Her grandfather has recently passed away, and her brother is missing, last seen working on the Liverpool docks. Everyone assumes him to be dead. But she will not give up hope. Ada's determined search takes her to the Crimea, where she joins the team of Florence Nightingale's nurses. She may have set off looking for her brother, but along the way Ada finds friends, romance and a new purpose in her own life in the most troubling and difficult of places.

England, 1941. After three nights of relentless bombing from German aircraft, trained nurse Jo Brooks is told to report to the basement theater of Mill Road Hospital. She goes with a heavy heart, not wanting to leave behind her best friend Moira, who is desperately soothing new mothers on the maternity ward. As Jo arrives safely underground, the ward takes a direct hit.

1914. Evie Munro is a Scottish fisher girl, working the herring season from Wick to Great Yarmouth. For Evie, every day is the same - gutting fish at the docks, shoulder-to-shoulder with her friends, followed by fresh bread, a warm whiskey toddy and an early night. But when Germany declares war, everything changes. As her village begins to empty of young men, Evie's life is marked by a heartbreaking tragedy. Her happiness destroyed, she vows to join the war effort as an army nurse, caring for wounded soldiers on the imposing hospital ship Britannic.

1940. Cora Mayhew came to Paris to search for her birth mother and stayed to work for the resistance movement. When Cora's train is struck by Nazi bombs, the only thoughts on her mind as she staggers from the wreckage are to escape to return to her family, and to post the heart-wrenching letter clutched in her hand. Then a German soldier finds and saves Cora. Max Heller is nothing like she would have expected: kind, good-humoured and selfless. Cora can't help falling in love with him as he helps to plot her escape.

1918, London. Twenty-year-old Emily Burdon has been training as a nurse at St. Marylebone Infirmary, learning on the job as she tends to patients from the crowded poorhouses that ring the hospital as well as wounded soldiers returning from the war. She pours her heart into her nursing while she waits for happier times - peace in Europe and the return of her childhood sweetheart, Lewis, from the Western Front. But when the deadly Spanish Flu arrives in London on the heels of the war, Emily’s faith and courage are put to the test.

1941. The Blitz rages over London. And even in Cornwall, the war is being fought. When Violet loses her sister in the Blitz, she must take her nieces to safety in Cornwall. On the coast, she meets carefree chorus girl Eva, who is also running from the dangers of London. But Porthcurno hides a secret military base, and soon Violet and Eva realise there’s a battle to fight in Cornwall, too. Together with local Hazel, who works on the base, they must come together to help the war effort. But will their friendship be enough to keep them safe?

Jane Hadley has nothing to lose when she runs away to join the Women's Auxiliary Air Force. Whatever faces her in war-torn London can't be any worse than staying at home with her abusive father. The city is nothing like she could have imagined, but she's soon on the move, travelling from base to base for her top-secret training. Making plenty of friends along the way, it doesn't take long for Jane to embrace her growing confidence - especially under the attentive eye of dashing Officer Oscar Stanton.

Flying instructor Ellie Simpson has grown up a tomboy. She's never had an interest in the latest fashions or finding a husband; her only passion is flying her beloved Tiger Moth. But when war is declared, she is no longer be able to do what she loves most - fly.

Following a humiliating experience involving the man she thought she’d marry, Iris Tredwick signs up to the Wrens in order to escape and - hopefully - find ‘the right sort’ of man to please her mother. After a bumpy start, Iris manages to befriend outspoken Mary and dreamer Sally as they are sent to their first posting - in Orkney. There she meets engineer Rob, whose flirtatious nature both charms and confounds straight-laced Iris. Much more appropriate for her is local doctor Stewart, if only she felt the same spark for him as she does for Rob.

Bristol 1939. At forty years of age, Mary Anne Randall still turns heads. With an abusive husband spending most of his wages on beer, she has resigned herself to be the sole breadwinner to protect her family and keep the wolves from the door. In order to make ends meet, Mary Anne runs a pawnbroking business from the wash house at the end of the garden. Following the outbreak of war an opportunity presents itself to escape her loveless marriage and find true love. Will she take that chance, or carry on living just for her children and not for herself?

Bristol 1936. Jenny Crawford has resigned herself to a loveless marriage living hand to mouth with their two children. Like many others, husband Roy struggles to find work at the docks but a chance encounter turns the family's fortunes around. Not only does he get regular work but they are also allocated a council house on Coronation Close on the outskirts of the city. Jenny and the children are overjoyed, this is the fresh start she could only ever dream of. But trouble feels never too far away.

The war has ended; the men are returning home to their loved ones, but for some, things have changed. Charlotte Hennessey-White's husband, David, is no longer the gentle loving man he once was and Charlotte, so independent during the war, is devastated. Edna Burbage's strong fiancée, Colin, has suffered appalling physical injuries. He won’t hold her to her promise of marriage, but she insists her feelings are unchanged. But is that true? And Polly Chandler's sweetheart, Gavin, who’d she’d planned her whole future around, hasn’t come home at all.

Alice Lake has arrived in London from Liverpool to start her training as a District Nurse, but her journey has been far from easy. Her parents think that she should settle down and get married, but she has already had her heart broken once and isn’t about to make the same mistake again. Alice and her best friend, Edith, are based in the East End, but before they’ve even got their smart new uniforms on, war breaks out, and Hitler’s bombs are raining down on London.

At the heart of Dover's Market Square lies the Castle's Café. A bustling, homely place run by the formidable Nellie Castle and her six children. Since the scandalous birth of her beloved son 10 years before, Marianne, Nellie's eldest daughter, has preferred to stay in the kitchen, hidden away from the town gossips. Overcome with shame, Marianne has never revealed the name of Donny's father - not even to her own mother. But with World War II just around the corner, Marianne's past catches up with her. And suddenly the lives of the Castle family become a lot more complicated.

Clara Newton is the new Housemother of Shilling Grange Orphanage. Many of the children have been bombed out of their homes and left without families, their lives torn apart by the war, just like Clara’s. Devastated by the loss of her fiancé, a brave American pilot, she is just looking for a place to start again. But the orphans are in desperate need of her help.