After the adventures of Four On the Run, Maxie, Flash, Lady and Fergie's lives have changed, because though they still live on the farm, they are now all spruced up and about to take part in their first film, The Famous Four. Part of it is set overseas and the four friends and Mrs Brown will be travelling to the set by a luxury cruise ship chartered by the film company. It's the first time any of them - including Mrs Brown! - have been at sea, and they are nervous and excited. Everything goes well - until the big storm. Washed overboard in their luxury container, the four friends find themselves landing on a desert island. At least, it seems deserted, at first... but soon they become aware someone else is there. Someone who is not very friendly - a rusty old tank that thinks there's still a war on! They need to escape from the island and get back to their ship and very worried Mrs Brown. ...but how?
