Without telling his mother, earnest teen Cameron impulsively follows his best friend Ray into the unforgiving gauntlet of Marine Corps boot camp.

A training exercise strains Cameron's bond with Ray and forces brothers John and Cody to unpack the family baggage they brought to Parris Island.

Cameron digs deep to prove himself in a confidence-building course. The platoon receives a late addition. Barbara discovers sympathy has its perks.

Amid a high-pressure week of swim training, Ray struggles to stay afloat - until Cameron dives in with a risky scheme to keep him above water.

Emotions run high as Cameron and the recruits aim to hit their marks in rifle training. Sgt. Sullivan lands in a very different set of crosshairs.

The platoon grapples with the cost of being a Marine. Capt. Fajardo brings Staff Sgt. McKinnon up to speed. The mess hall lives up to its name.

As combat training begins, a brutal mind game drives a recruit to the breaking point. A violation of protocol stirs trouble in the ranks.

The recruits face the ultimate test as the Crucible pushes the limits of their endurance - and brotherhood is the only way to get past the finish line.