Best friends Millie and Jess look just like twins! Millie is a princess and Jess is a maid so they have lots of fun swapping dresses and going on adventures around Peveril Palace. When a priceless painting is stolen, can the girls work out why and who is responsible? Don't miss the girls' first, second and third adventures - THE CASE OF THE STOLEN CROWN, THE SECRET OF THE SILK DRESS, THE MYSTERY OF THE LAKE MONSTER.