Evie and Maryam are in the same class at school but aren't friends, until they are paired up for a project to investigate their respective family histories.

Both girls have already discovered that their grandmothers possess a red folder full of letters written in a strange text. It's not English and they don't think it's Urdu or Hindi either. They're curiousity causes the girls to overcome their differences, slowly. Maryam is an outsider, bullied and ridiculed for her family background, and Evie is keen to remain popular with the other girls in class.

The story alternates in time periods from the present day, with Evie and Maryam and their detective work and growing friendship, to the 1920s and 30s in India. Here the girls' great-grandmothers Kathy and Safia are also deepening their bond of friendship with the challenges facing them through their different backgrounds and the political situation of the partition.

It's a beautifully told story about family and friendship, history and prejudice, cultures and class. The characters are engaging and there's also a link to Bletchley Park. Much to enjoy here.