This story is set before 'Peter Pan', Peter has just recently gained his ability to fly and never grow old from a substance called 'starstuff'. Every so often starstuff falls from the sky, and many types of people and creatures are after its uncanny powers. Starstuff can do all sorts of things, many of its powers are not even known.
One set of creatures after the starstuff are called the Others. They are the 'bad guys' who will stop at nothing to acquire the power held by the starstuff. The Others have a creature on their side that is unlike anything. This creature calls himself Lord Ombra. When Lord Ombra touches a person's shadow the shadow goes to him, detaching from the person. One of the characters, Molly, says it this way: "there's a shadow man, I don't know how he does it, but somehow he takes people's shadows, and then he controls them."
Another set of people after the starstuff are the 'starchatchers'. These are the 'good guy's" who give the starstuff back to the sky. Molly and her parents are some of them. The starchatchers have been doing this for centuries; and the Others have been trying to prevent it for centuries.
*This book is a sequel to 'Peter and the Starcatchers,' a fact I didn't realize this until I had finished it. I believe that 'Peter and the Shadow Thieves' can be read alone, but would probably be better understood if read after its prequel.*
Here is a taste of the inside cover:
Peter leaves the relative safety of Mollusk Island- along with his trusted companion, Tinker
There was one formatting issue that annoyed me. There are two, sometimes three, stories going on at the same time. As soon as some nerve-racking or cliff-hanger chapter finishes, the authors switch stories for a chapter or two. It was very annoying at first, but as the book went on it was evident that it helped the story. It really keeps you reading until the last page.
This book also has one of the best end-lines ever. It makes you smile as you close the book. The last sentence in the book is only two words, but it is the best ending the story could have gotten.