The Andorians and the Vulcans are locked in battle over a small planet—the Andorians refer to it as "Weytahn," the Vulcans "Paan Mokar". Situated on the frontier between their two systems, it is claimed by both sides. Andorian Commander Shran has broken the treaty and reoccupied the settlement. With the Vulcans calling for a cease fire, Shran seeks Archer's neutrality to help negotiate. Vulcan Ambassador Soval is reluctant to bring Archer in as mediator, but three Vulcans have been taken hostage, and Shran has made his position clear—he only trusts Archer, particularly since the incident on P'Jem.
Archer and T'Pol head down the planet for a meeting with Shran. His lieutenant, Tarah, is especially wary of Sub-commander T'Pol, but Archer manages to convince Shran to release one of the hostages as a sign of good faith. He also agrees to bring Soval down to the planet for a meeting. Soval is skeptical, but finally agrees to go. Meanwhile, on the planet, Shran has a tense moment with Tarah, who objects to his attempts to negotiate with the Vulcans. She would rather fight, after a century of negotiations and treaties, and reclaim the planet for the Andorians.
As the shuttlepod nears the planet, Archer, T'Pol, and Soval are fired on and are forced to crash-land. Soval suggests the Andorians are trying to sabotage the peace talks, but Archer doesn't believe Shran would resort to such tactics. Shran is furious that Archer's shuttle was downed, but Tarah claims that it was the Vulcans trying to frame the Andorians. Shran orders her to find them and bring them to him alive. Meanwhile, on Enterprise, acting-captain Tucker is having troubles of his own - he must keep the Vulcan and newly arrived Andorian vessels from firing on each another. To do so, he maneuvers Enterprise between the two groups.
Down on the surface, Archer, T'Pol and Soval are attempting to make their way to Shran's location, when Soval is shot. Archer discovers that renegade Andorians are behind the attack, and captures Tarah, just as Shran and his men arrive on the scene. Even though Tarah initially denies it, she eventually confesses, and angrily informs Shran that there are others who feel the same way. With the situation under control, Shran and Soval are finally able to meet. Back on Enterprise, with Archer's help, the two sides agree to a ceasefire, and continued peace talks on Andoria.