The eleventh book in the laugh-out-loud series from Pamela Butchart!
Izzy's school is being merged with St Bartholomew's Primary, their greatest rivals! What will happen when the new kids join, in their too-shiny shoes and with their too-loud singing? And what if they've got a secret mission and that mission is a BAD mission? Only Izzy and her friends can discover the truth, even if they must go SO DEEP UNDERCOVER that they might not come back...