Picts and the Martyrs

The dreaded Great Aunt has invited herself to stay with Nancy and Peggy just as their friends Dick and Dorothea arrive for the Summer holiday. Nancy and Peggy have to become Martyrs, wearing dresses and reading poetry (but breaking out at night), while Dick and Dorothea become Picts, secret inhabitants of the country who must never let themselves be seen. It's a desperate gamble to keep everyone out of trouble - but can it possibly work against the eagle eyes of the fearsome Great Aunt?