Submarine Spy — Arnold Ytreeide

The adventures of Mike and Josh begin as the two seventeen-year-olds launch their dream -- and run straight into trouble.All Mike Danford wants to do is build his own submarine. It's a big job for a teenager, but with his best friend Josh Roberts he's making it happen. But somebody doesn't like what they're up to and is trying to stop them. Mike is sure he knows who it is, but no one will believe him. As the boys defend themselves against constant sneak attacks, they launch the sub -- and launch themselves into events that threaten their lives! Only with the help of their parents, the Navy, and the grace of God can the two survive . . .Though it's not absolutely critical, readers will get the most out of this series by reading it order since themes, new friends, new inventions, and issues of faith grow from book to book.