It is based on the true and factual events of the Libby prison break in 1864. From what I could find the main details are all true, obviously I am sure the dialogue is fictionalized. But one of the escapees later wrote a book about his escape so there is at least some great source material.
There was on instance of swearing, "I'll be damned if I stay here."
A couple references to "rat hell". This was in the cellar and they had to walk over the rats to get to their tunnel site.
There are also gross descriptions of their living conditions, such as food covered with maggots, a trough for a toilet, rats, lice racing, etc. as well as descriptions of violence. One prisoner when he is being recaptured, picks up a gun and smacks his warden with it in defense.
And this is just personal but there was one section where it talked about why the north and south started fighting that it was over slavery. I didn't personally appreciate the over simplification. But again just personal.
Over all I liked it. If your kiddos like "Nathan Hale's Hazardous tales", or the "I survived" series they would most likely like this one as well. I don't know about any pictures as I listened to it, but I'd say it was written for the middle-lower grades, maybe 8-12 range so I'd bet there were some pictures.