Cry Havoc

In May 1968, US Navy SEAL Thomas Reece and his MACV-SOG (Military Assistance Command, Vietnam - Studies and Observations Group) unit, Recon Team Havoc, are on a wiretap mission on the Ho Chi Minh Trail in Laos. Led by Army Special Forces veteran Frank Quinn and Vietnamese interpreter Hiep, the team is detected by an NVA (North Vietnamese Army) hunter-killer unit. During a fierce firefight, Tom detonates a chain of claymore mines and the team begins a fighting withdrawal. One of their Montagnard mercenaries, Sau, is critically wounded, and Tom carries him. Their first helicopter extraction is ambushed at a pre-sighted landing zone. During a second attempt using ropes, Tom's gear becomes entangled in the trees, nearly strangling him. As he frees himself, he witnesses the second helicopter carrying Quinn's squad get shot down. Believing Quinn may have survived, Tom cuts his own rope and falls back into the jungle.

The narrative shifts to four months earlier, January 1968. The USS Pueblo, an American spy ship under the command of Commander Lloyd "Pete" Bucher, is collecting intelligence off the coast of North Korea. Concerned about the ship's inadequate means of destroying classified material, Bucher's fears are realized when North Korean naval vessels and MiGs attack the ship in international waters. Unable to effectively destroy their sensitive crypto machines and documents, and facing the slaughter of his crew, Bucher surrenders the vessel.

In Moscow, GRU (Soviet military intelligence) Director Mikhail Lavrinenko briefs cryptologist Sergei Egorov on the intelligence windfall from the captured Pueblo. Egorov explains the crypto machines are useless without current keying material. Lavrinenko reveals the GRU has two sources for these codes: US Navy Warrant Officer John Walker and an NSA asset, Allister Desmond, who is being handled by a Stasi agent, Clara Müller. Lavrinenko decides to send Müller to America to retrieve new keys directly from Desmond. In Maryland, Desmond, an NSA employee motivated by the thrill of an illicit affair with Clara, copies keying material using a rotor reader device.

Back in Vietnam in late January, Tom, Quinn, and their Montagnard leader, Amiuh, conduct an unauthorized mission near their base at Phu Bai. They ambush an NVA patrol and capture an officer who is a courier. Their commanding officer, Lieutenant Colonel Konrad Backhaus, retroactively approves the mission and orders them to escort the prisoner to Da Nang. Tom gives his Seiko watch to Amiuh, who is disappointed not to have received one as a reward. Amiuh's most prized possession is a Croix de Lorraine rosary.

In Moscow, GRU Major Kirill Dvornikov proposes a new strategy: using the intelligence from the Pueblo to target and capture MACV-SOG operators in Laos. The captured Americans will be secretly transported to the Soviet Union for interrogation. Lavrinenko approves and arranges for a brutal Spetsnaz operative, Adrik Voronin, to be released from a Hanoi prison to act as Dvornikov's enforcer.

In Da Nang, Tom and Quinn learn their prisoner is repeating the phrase Crack the Sky, Shake the Earth and are ordered to escort him to Saigon. Dvornikov, learning the prisoner knows details of the upcoming Tet Offensive, arranges his assassination. The convoy is ambushed in Saigon. The traitorous ARVN (Army of the Republic of Vietnam) escort, Captain Lam, executes the prisoner. Tom and Quinn kill Lam, but their teammate Amiuh is killed driving them out of the ambush.

Afterward, Colonel Singlaub, the Chief of SOG, introduces them to CIA officer Nick Serrano. Singlaub reveals a personal connection to Tom's father, whom he knew from their shared time in the OSS (Office of Strategic Services). Serrano reveals the prisoner's satchel contained maps and hit lists for the Tet Offensive. At the CIA annex, Tom meets and is captivated by Ella DuBois, the daughter of a prominent French-Vietnamese businessman, Gaston DuBois. When the Tet Offensive begins, Tom and Quinn's safe house is attacked. Serrano recruits them to rescue Gaston and Ella from the Majestic Hotel, which they successfully accomplish.

The narrative returns to May 1968. After falling back into the jungle, Tom tracks the captured Quinn and Hiep to an NVA depot. There, he witnesses the Soviet advisor, Voronin, brutally torture Quinn before being forced to escape. Enraged, Tom attacks the camp with a captured antiaircraft gun, destroying its vehicles and fuel supply before escaping. After a multi-day evasion down the Sepon River, he reaches South Vietnam and convinces Colonel Backhaus to launch an immediate, unauthorized rescue mission. The SOG raid finds the depot empty; the prisoners have been moved. They discover Quinn's decapitated and disemboweled body tied to a tree, with his own tomahawk pinning Amiuh's rosary to it.

By July, while Tom is recovering in Da Nang, Serrano reveals the CIA has identified a GRU spy network and has unconfirmed intelligence that the Soviets are moving American POWs to Siberia. The network involves State Department liaison Dan Eldridge passing information to a cutout, Lan Tri Phuong, who relays it to a French doctor, Jean René Brémaud. Brémaud uses a dead drop serviced by Ella DuBois, who acts as a courier for her GRU handler, Dvornikov. Serrano officially transfers Tom to the CIA to help dismantle the network.

Tom and Serrano kidnap Ella and turn her by implicating the GRU in her father's recent assassination at the Cercle Sportif club. In Bangkok, the plan to capture Dvornikov is complicated when he arrives with Voronin as security. Ella proceeds with the plan to drug Dvornikov, but Voronin is waiting in her hotel room and kills her with a silenced pistol. A firefight erupts, and Tom and Serrano pursue the two Soviets in a longtail boat chase. Tom rams their boat, captures the drugged Dvornikov, and maims and captures Voronin, whom he recognizes as Quinn's killer. On a derelict trawler, Tom tortures and kills Voronin in the same manner as Quinn, forcing the terrified Dvornikov to confess everything about the POW rendition program.

In the aftermath, a series of events unfolds. In Moscow, GRU deputy director Anatoly Penkovsky is exposed as a CIA mole and executed. To protect a more valuable asset, Lavrinenko arranges for the FBI to arrest the lower-level spy Allister Desmond. In Saigon, Dan Eldridge is found dead in an accidental drowning arranged by Serrano. Serrano explains that the US government has brokered a quiet deal: the entire crew of the USS Pueblo will be released in exchange for Dvornikov's return and American silence on the POWs in Siberia.

On New Year's Eve 1968, Serrano sends Tom on a final mission to Berlin. With help from the Army's clandestine Detachment A, Tom infiltrates East Berlin and ambushes Dvornikov in his apartment. After Dvornikov refuses to cooperate, Tom executes him with the same type of silenced pistol used to kill Ella. Tom then decides to return to Vietnam to work with Serrano in the new Phoenix Program, continue the hunt for American POWs, and find Amiuh's son.