
The mission of Commander George Krause of the United States Navy is to protect a convoy of thirty-seven merchant ships making their way across the icy North Atlantic from America to England. There, they will deliver desperately needed supplies, but only if they can make it through the wolfpack of German submarines that awaits and outnumbers them in the perilous seas. For forty eight hours, Krause will play a desperate cat and mouse game against the submarines, combating exhaustion, hunger, and thirst to protect fifty million dollars' worth of cargo and the lives of three thousand men. Acclaimed as one of the best novels of the year upon publication in 1955, The Good Shepherd is a riveting classic of WWII and naval warfare from one of the 20th century's masters of sea stories.
I just looked and it looks like there are two books by Forester. One is The Good Shepherd which is the original book and the other is Greyhound which is also by Forester and is sold as the movie tie-in. They have different number of pages, so I assume they are different.
Edit: I ended up buying The Good Shepherd because it was only $0.99 for the ebook.
