There's a lot of past, and there's getting to be more and more of it every minute.
Richard and Cynthia Weatherspoon, aged ten and eight ("and three-quarters"), are living as (step)brother and sister in the midtwentieth century. But when they and their parents call on old Granny Ogden, the children discover that when they unlock Mrs. Ogden's back door, a path appears that simply isn't there to anybody else.
They walk down the path with their dog, Timmy, escorted by a Magpie, and find themselves in the days of the Model T Ford where they meet their grandparents and sinister villains are foiled.
As the children get older, through their early and later teenage years and early adulthood, subsequent travels down the path with other birds as escorts take them to earlier and earlier timesto the days of the first steam engines, the days of Charles I, the Elizabethan age, and earlier, mediaeval times. Some wolves, travelling minstrels/players, would-be bandits, a Scots prince, and a mysterious relative all appear in the action as Richard and Cynthia with Timmy, and their avian escorts seek to free a princess from a fate worse than death at a sinister baron's castle.
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