Walking Shadow summary:
It is twenty years after the end of Silver on the Tree, and the characters have long since lost touch.
Will is gradually withdrawing from the world, and in the story's first scene, he removes himself from the memories of his entire family. He is tormented by the fact that there are evils in the world, but he is supposed to stand by and watch, letting man make his own choices. He can't even talk to Merriman, because the Old Ones have all gone out of time. In practice, this means that Merriman and the others cannot see Will, even if he goes back to times when they were.
Jane, a teacher, is obsessed with memory, because she is haunted by the feeling that she once forgot something very important. Bran is still farming in Wales, but he, too, is far from content. He is sure that once he actively chose this life, but he can't remember how, or when.
One night, Bran is attacked on his doorstep. The next day, Jane is almost attacked, too, but Will saves her. (Will regularly visits his former friends, to watch them from hiding.) Jane is fascinated by this mysterious stranger who has saved her life. When he leaves, saying he's off to Wales, it reminds her of the holiday she once had in Wales - a holiday that is, perhaps, the source of her mysterious memory problems. She goes to Wales, too.
In time, all the characters come together, but Bran hates Will on sight. Partly this is because of jealousy over Jane's regard for Will, but mostly because events have caused him to believe that Will was behind his attack.
Will learns that some unidentified enemy was behind Bran's attack, and that Bran was targeted only as a way to get to Will. Will swears to face this enemy head on, and defeat him… but the enemy does not show himself. Will gets increasingly despairing about his failure to track down his enemy, and from Bran's increasing hostility. Whenever he is at his lowest ebb, a man called Mark appears, saying just the right thing…
Meanwhile, fights and murders are breaking out all around, and ghosts of people long dead play out their final moments on the mountain. The spirits of long-dead chieftains rise, and are strengthened by Will's blood, shed when he carelessly went back in time in an attempt to stop a long-ago murder.
Jane sees enough strange things to make her receptive to the truth. She puts two and two together, and realises Will is a wizard. She confronts him, and he confirms it, and also confirms that he (or, rather, Merriman) was behind her lost memories. When she tells Bran, he, too, confronts Will, but only to hate and accuse him.
Will is left alone, when Mark appears, and reveals that he is the enemy. The enemy is a spirit born of the darker emotions of man throughout the history of mankind. The twin poles of Light and Dark more or less held it in check, but now it is growing. It can get into people's minds and exacerbate their dark emotions. It can also fully occupy a dead body, which is how it is currently in the body of Mark, a dead climber.
The enemy's influence almost causes Will to destroy himself, but Jane and Bran return. Bran is still hostile, but strangely his hate-filled words have more effect on Will than Jane's kind ones. Together, they cause Will to remember that he is human as well as an Old One, and that he is part of the world.
Will resolves to fight the enemy and destroy him, and Bran and Jane promise to help him. First, though, Will returns to his family and restores their memories...