Subtitled 'The True Story of the Legendary WWII Battalions".
This book, of course, is a history of the four USMC Ranger batallions. The trining is not described in detail but is noted to be 'harsh'. But it made these young men tough. Their various campaigns are described by following several men who were able to be interviewed or for whom there was very good documentation. the Long Patrol of Guadalcanal is detailed.
It's a very interesting book if you care to read WW2 history.
I knew a Raider many years ago. He had some very interesting stories that he shared.