David is a 13 year old whose father disappeared six months ago and is presumed dead. Before he disappeared, though, he was acting very strangely, wandering off for days at a time, and talking baby talk. David is just coming to terms with what happened, when he's riding a subrail (subway) with some friends and sees his father on a platform that doesn't exist, with people that nobody else on the train can see. Of course, David has to investigate, which leads to more questions than answers.

I thought this was a good book with an interesting premise. It was a bit confusing, but things are explained by the end of the book, which then left off with a cliffhanger. You have to read it to understand this.

This was actually a short book, but it's part 1 of 6, which I think will keep the age group it's recommended for, 8 to 12 years old, interested and get them to keep reading because it is not an overwhelming length.

In summary, I enjoyed this book and think 8 to 12 year olds would find it intriguing.

4/5 stars.

I received a copy of this book free of charge in exchange for my honest opinion.