The Shadow People

When both the school bus and Sarah Jane's car break down in Snowdonia, the gang find themselves stranded in the middle of nowhere.

Exploring by a lake, Rani sees a shadowy figure that looks exactly like her. Then Sarah Jane hears a voice asking for help, and sees a mysterious figure outside her tent. Who is watching them, and why? How can Rani be in two places at once? And what secret does a nearby cave hold?