Love is in the air, and together the railway girls can overcome even the hardest of times. Mabel has finally put the past behind her, and her relationship with the dashing Harry is stronger than ever. That is, until an old flame shows up, leaving Mabel questioning her future. Meanwhile Joan has made amends with Bob - if only she could do the same with Gran. And there's still that family mystery she wants answer to, isn't there? As a mother and grandmother, Dot Green has always put her family first. Her job as a parcels porter has brought new purpose to her life, so is it finally time to start following her heart . . . Life as a railway girl is busy but as war rages on and air raids disrupt daily life, the women realise they need each other more than ever, especially when there might be wedding bells on the horizon.