8404 is the United States Navy designation for a Corpsman, Sailors who provide medical care for Marines while on mission. There's a special bond between Marines and Corpsmen, more affectionately known as 'Doc.' Dominic Villanueva, however, has been through the ringer. He's saved Marines and lost them. Now he struggles to hide his feelings of inadequacy while continuing his deployment in Afghanistan.Christopher Bast is a combat veteran of the United...