T'Pol, Malcolm Reed and Hoshi Sato are stranded on a Klingon ship sinking into a gas giant. Captain Jonathan Archer tries to convince a captured Klingon to help before the away team is crushed by the intense pressure of the planet's atmosphere.
The Enterprise drops out of warp near a class 9 gas giant. Upon scanning the planet, the crew locates a power signature in its lower atmosphere, as well as several bio-signs. Hoshi, T'Pol and Reed (who is suffering from a cold) take a shuttle to investigate and discover the Klingon vessel Somraw, which is estimated to be about one hour from being crushed by the planet's atmosphere.
Once docked, T'Pol finds three unconscious Klingons on the bridge. She leaves them to die at their posts, assuring them a place in Sto-Vo-Kor, the Klingon afterlife for the honoured dead. More scans detect residual elements of a carbon dioxide-based neurotoxin. Bu'kaH, a Klingon woman who had been observing them, knocks Reed over and escapes in the away-team's shuttle-pod. The Enterprise traps the shuttle-pod, but not before Bu'kaH broadcasts a distress signal. They attempt to bring the Enterprise down to rescue the away-team, but the pressure is too high. Instead, they start reinforcing a shuttle-pod to withstand the pressure, and request Bu'kaH's help, which she refuses to provide.
Meanwhile, Hoshi translates the consoles to find the Engineering, Tactical and Helm stations. When she finds the Captain's log, it states that the ship was damaged in a skirmish with the Xarantine, and that the Klingon Captain ordered his ship into the gas giant's atmosphere to effect repairs. The Captain then says that it would have been better to be destroyed rather than to fall prey to a disease. Hoshi locates the port fusion-injector on a schematic, and the Away Team make their way to Engineering to attempt repairs. On board the Enterprise, Archer talks to Bu'kaH in sick bay. Dr. Phlox has discovered that the neurotoxin was bonded to a molecule in Xarantine ale, which Bu'kaH confirms was part of their spoils. He convinces her to help, citing the crew's dishonourable deaths.
On the Somraw, Reed uses shock-waves from photon torpedo in an attempt to raise the ship and lower the hull-pressure. This also allows Archer and Bu'kaH, in the reinforced shuttle-pod to find them. Archer tells Bu'kaH that his away-team risked their lives for her ship, and that he isn't leaving until the ship is safe. Archer arrives on the Enterprise's Bridge as the recovered Somraw hails. The Klingon Captain orders Archer to surrender the Enterprise as punishment for violating his ship. Archer faces down the Klingon Captain, telling him that his ship is weak and nearly defenseless, and that if he fires on the Enterprise then Archer will put him back where he was found. The Klingon Captain snarls and ends transmission before moving off.