A monster ate my Marmite

de Eric Brown

"Mouse, Millie and their alien friend Umba-Wumba travel back to the year 1400 to research knights and dragons for their homework. But their trip doesn't go as smoothly as planned when they get roped into saving the villagers from an evil monster! Aided by the worst knight in England, can the trio fulfil their mission and make it back home?" --Publisher.