The Mystery of the Flying Toilet is the third tale in the Crust Sisters series. In this new adventure, packed with humour and winks to modernity, the Crust sisters travel to New York for the International Granny Detective Conference, the most important in the world for any investigating granny. The Plaza Hotel is packed full of famous detectives, the Tiatrappo sisters from Italy, the Akí Mekedo from Japan, and even Donald Trumpet himself. But amongst all the excitement there is a mystery: the paper from the hotel toilet has inexplicably disappeared. The sisters, Marcel and their new friend Max must follow the clues to solve the case. Who is the guilty party? Anna Cabeza's series is accompanied by illustrations from Toni Batllori. It has sold over 15,000 copies and has been translated into four languages. The next book is published in February 2022.