Peter's life in Stargazers Valley is one nestled in routines of helping his parents run their guesthouse, looking after/chasing after his younger siblings, drinking hot chocolate at the local cafe with his best friend Linnet, and looking up at the night sky lit up with Skeins of starstuff, beautiful and magical, telling the stories of the Spinner and the Weaver and the mischievous Jackanapes up in the stars to his little brother. He's used to visitors, who are almost always there to climb the mountains or to investigate the starstuff that falls on them, and so when he meets a pair of older travelers on the road, pulling a cart heaped full of miscellany behind them, he is quick to direct them to the family's inn. These tinkerers are researchers from the Imperial College, but they aren't like any Peter's ever met before, and they don't exactly become friendly with their colleagues already in residence....
There's a reason for this, carted along behind them on their way to the valley. Starstuff can do magical, wonderous things, and so it is a tightly controlled substance that only a very few are allowed to manipulate and experiment with. And no one is allowed by the Empress to make, say, a tinkered together device that can turn back time....When Peter figures out what the tinkerers have brought with them to the inn, he can't resist the temptation to fix small mistakes...no one notices, and life goes on, but better. But then, when the biggest mistake of his life, made years ago, threatens his family, turning back time seems the only way out...
I started reading this (mostly) cozy fantasy back in May, but then life got messy, and I didn't want my enjoyment spoiled. So I started from the beginning again a few weeks ago, and did not in the least bit mind re-reading the first 200 pages. This is one for those who like fantasy with young protagonists who are realistically having concerns more germane to the young (which is why middle grade fantasy is better escapism than books for grown ups.)