Puffin Books, London, 2004, 178 pp.
Tamzin Weston and her guardian pony Moonlight are preparing for the pony Fun Day. However, all is not right: there’s a strange rider and pony there, Marga and Lossie. Marga takes Tamzin’s protective talisman, and arranges things so that Tamzin has to ride Lossie. Lossie heads for the cliffs, out of control – and after Moonlight rescues Tamzin, Marga and Lossie disappear. Tamzin knows they must have been agents of the Grey Horse, and that he won’t give up.
The Sea Horses series
The Last Secret