They call them the custard tarts - the girls who work at Pearce Duff's custard powder factory in Bermondsey before the First World War.
Conditions are hard but nothing can quench the spirit of humour and friendship - or the rising tide of anger that will finally bring the girls out on strike for a better deal. For one of them, striking spells disaster. Nellie Clark's wages keep her young brothers and sister from starvation, while her father sinks into drunken violence after the death of their mother.
And over them all looms the shadow of the coming war, which will pull London's East End together as never before - even while it tears the world apart.