Thirteen year old Erin loves horses and riding. After dreaming of the Bronze Age horses, she is starting to like history.
Now curious about Ancient Greek horses, Erin again drifts into an opal dream.
Agis, a teenage boy, travels alone from Sparta to Athens where Diodorus gives him work at the stables. Agis earns the trust of a vicious black stallion, but is targeted by the jealous, Tellus. When the stallion escapes, Agis is suspected and threatened with punishment of death or slavery. Will Agis keep his freedom and survive to fulfil his dream of riding a horse?
When Erin wakes from her dream, she realises she can use what she has learnt about horses from the Ancient Greeks.