The Presidio

MP Patti Jean Lynch is shot dead while investigating a break-in at the Presidio Army base in San Francisco. This tragic event also results in the deaths of two San Francisco Police officers during the getaway, marking the beginning of a complex investigation.

San Francisco Police Inspector Jay Austin is called in to investigate the murders. Tensions rise as he clashes with Lieutenant Colonel Alan Caldwell, the base Provost Marshal and a figure from Austin's past.

Years prior, Austin and Lynch were partners while serving as MPs, with Caldwell as their commanding officer. A past incident involving the arrest of Colonel Paul Lawrence leads to animosity between Austin and Caldwell when Austin is demoted and leaves the army.

The investigation reveals that Lynch was killed with a Tokarev, a Russian pistol, owned by Colonel Paul Lawrence. Although Lawrence claims he lost the weapon, Austin grows increasingly suspicious of his involvement.

Austin and Caldwell realize that the case is split between their jurisdictions, leading them to form an uneasy partnership. They agree that matching the bullet from the crime scene to Lawrence's weapon could lead to an arrest.

Austin and Caldwell question Arthur Peale, the owner of the getaway car linked to the crime. Peale claims his vehicle was stolen and provides an alibi, but Caldwell suspects hidden ties to the ongoing investigation.

The ballistics report confirms that Lawrence's Tokarev was used to kill Lynch. Ignoring his agreement with Caldwell, Austin confronts Lawrence, resulting in a dramatic foot chase through San Francisco's Chinatown.

The foot chase ends tragically when Lawrence is killed in a hit-and-run incident. This event escalates the already tense relationship between Austin and Caldwell, complicating their investigation further.

Caldwell’s personal life becomes entwined with the investigation as he struggles with his daughter Donna's rocky relationship with Austin. This adds emotional weight to the already strained interactions between the two men.

Austin and Caldwell trace the investigation to a water company linked to George Spota, a driver with connections to the murdered Colonel Lawrence. This connection uncovers deeper affiliations involving their respective pasts in Vietnam.

As the investigation unfolds, it becomes clear that the murders are part of a larger conspiracy involving diamonds being smuggled in water bottles. Austin and Caldwell discover that Spota actively participated in these criminal activities.

Caldwell and Austin confront a shocking scene at the water company where they find Peale and Spota involved in the smuggling operation. The situation escalates as they learn about the past connections with Maclure.

A violent gunfight erupts at the water company as Caldwell and Austin attempt to save Maclure from Peale's men. In the chaos, Maclure is fatally wounded while trying to stop the operations that caused Lynch's death.

In the aftermath of the violence, Caldwell asks Austin to delay his report for 48 hours to allow for a proper military burial for Maclure. This request emphasizes the bond developed amidst their tumultuous relationship.

The film concludes at a military cemetery, where Caldwell tearfully delivers a eulogy for Maclure. The conclusion also hints at reconciliation between Caldwell and his daughter, as well as a begrudging acceptance of Austin into the family.