A power cut and a series of mini disasters means friends, Jess, Nadia, Tomma and Ash barely make it to the station to catch their train to school. What they find is a far cry from the usual packed commuter train they're expecting...

When they arrive at Hickley School, the children are surprised to find some of the buildings missing and they don't recognise any of the other pupils, who are all dressed in a different style of uniform. The only person who takes the time to help them is Martha, despite being preoccupied by her own worries about her family being hungry and not hearing from brother, Henry whom she says is away fIghting.

The children soon realise this is no normal day and it's not until they return home that they're able to figure out what happened. What they don't know is whether it was a one-off day, or if they will get to see Martha and the other pupils again. Jess hopes so. She has something she needs to tell Martha. Not knowing how or why, she feels a connection and an obligation to this girl she can't explain.