2 Sarah and 2 tom,David: Sarah's boyfriend, a 30-year-old, Emma

2 Sarah and 2 tom,David: Sarah's boyfriend, a 30-year-old, Emma: Sarah’s younger sister, 2,Rachel: Emma’s best friend, 23 years David picks up the camcorder, filming the empty streets outside. “We’ll keep going,” he says, more to himself than to the others. “We’ll find somewhere safe.” But even as he says the words, he knows that safety is becoming an increasingly elusive concept.