On a bright May morning, 5,000 sailors and Marines bid farewell to their loved ones before the mammoth USS Nimitz pulls out of Coronado, California, and sets a course for Hawaii and beyond. Among the men and women who live and work on board are an airman who describes the ship as a small town; a pilot who considers the ship a powerful instrument of diplomacy; a sailor who questions “why we’re fighting to defend someone else’s freedom when we barely have our own”; a cook who dishes out 15,000 meals a day; and an airman who has just learned that his girlfriend is pregnant.

The men and women of the USS Nimitz live beneath the runway of a major airport. They sleep on the roof of a nuclear power plant. It’s a perilous environment. Their only bulwark against danger and chaos is to bond with their units on board the ship. The “Shooters,” who launch the jets, have a “Circle of Trust”; the Ordies (ordnance personnel) pride themselves on being a “mafia”; the F-18 squadrons — the Black Aces, the Hoboes and the Marine Red Devils — are tight fraternities.

The ship’s location and itinerary are classified. Details of how the nuclear reactor works are top secret. Many aspects of life on a nuclear aircraft carrier are hush-hush. Dating and sex aboard ship are strictly forbidden, but according to one sailor, with 5,000 people on board, relationships are “inevitable,” resulting in a “don’t ask, don’t tell” policy that applies to relationships as well as sexual orientation. When the Nimitz pulls into Hong Kong for a four-day port call, a scandal dramatically alters the lives of two sailors. As the ship departs, the crew learns their itinerary has changed. The captain announces that they are heading for Korea, but the crew can’t share this information with their families back home ... because it’s a secret.

Mentoring and camaraderie are what hold the ship together. But life on deployment is stressful for everyone aboard, and there can be considerable friction between enlisted personnel and their superiors. Port calls allow sailors to blow off steam, but they don’t relieve all the pressure. In Guam, a young sailor coming to terms with his upbringing can’t play by the rules and is forced out of the Navy. From Guam, the Nimitz sails through the Straits of Malacca, past Singapore to Kuala Lumpur, the last liberty call before the long haul to the Persian Gulf.

The mission really kicks off when the Nimitz arrives in the Gulf. The conditions are extreme: flight deck personnel endure temperatures hovering around 120 degrees, while the pilots undertake grueling six-hour missions over Iraq. The F-18s are mounted with infrared cameras, enabling them to serve as the “eyes in the sky” to support the troops on the ground. Some of the pilots are frustrated that they’re not dropping bombs because, as they describe it, that’s what they’ve been trained to do. The aircraft carrier’s role and effectiveness in this particular war are questioned. Meanwhile, the strike group searches for terrorists on small dhows and intercepts cargo ships to search for weapons and bomb-making materials.

After two months in the Gulf, one day starts to become indistinguishable from the next. The airwing still hasn’t dropped a single bomb, which is frustrating for some on board. The only relief comes from a port call in Bahrain, where some sailors relax by the pool, while others visit a mosque and learn about Muslim culture. The Princeton, one of the escort ships in the Nimitz strike group, loses a man overboard; an intense search to find the lost sailor ensues.

The last day in the Gulf is the last chance to drop bombs before the Nimitz heads home. The jets take off, laden with ordnance, and return hours later, still carrying the same bombs. As the Nimitz crosses the equator, the entire ship takes part in the Crossing the Line Ceremony, an ancient maritime ritual. In the middle of flight operations, a storm arises in the South Indian Ocean. The deck pitches violently, turning the already dangerous task of landing on the carrier into a nail-biting, heart-pounding drama.

This episode explores the many expressions of faith onboard the USS Nimitz: faith in self, faith in one’s shipmates, faith in the mission of the ship and the president’s call to arms. The major religious groups on board are Catholic and Protestant, but there also is a coven of Wiccans, as well as a Pentecostal group whose newest member is challenged by the duality of his beliefs and the temptations of liberty as the ship drops anchor in Perth, Australia.

A six-month absence places a heavy burden on relationships. The Navy holds seminars to counsel sailors on what to expect when they return home — and how to make the transition smooth. The “Tiger Cruise” ritual allows sailors to invite their family members aboard for the last leg of the deployment.

As the Nimitz makes its final transit from Hawaii to California, the sailors and Marines on board prepare to return to their homes and families. For those still on board, the “Tiger Cruise” provides a buffer, but there’s no such transition for those who fly home early from Hawaii. As the Nimitz returns to her home port of San Diego, sailors and Marines reflect on the deployment and take stock of what they’ve achieved. Was the mission accomplished? There are tearful, joyful reunions at the pier.