Equinox (Star Trek: Voyager)

USS Voyager's crew is surprised to receive an emergency hail from another Federation starship, the Equinox, in the Delta Quadrant. They arrive to find the damaged ship under attack by nucleogenic lifeforms. Under advice from the Equinox captain, Rudy Ransom, Captain Kathryn Janeway has Voyager extend its shields around both ships, quelling the attack, though the creatures continue to bear down on the shields, weakening them over time.

Janeway and Ransom discuss how both their ships had been pulled into the Delta Quadrant, five years earlier, by The Caretaker. Ransom shares that they found a wormhole and made enhancements to their warp engines, explaining how this allowed the smaller and slower Equinox to travel the same 40,000 light years as Voyager on its return to Earth. Of Ransom's crew, only 12 are still alive.

While surveying, Voyagers crew finds an area of the ship they cannot access due to intentional overrides by the Equinox crew. Janeway sends the holographic Doctor to the area, where he finds the Equinox crew has been harvesting bio-energy from the nucleogenic creatures, slaughtering dozens of creatures just to enhance their warp drive, traversing 10,000 light years in two weeks.

The Equinox crew know that they can reach Earth within weeks if they use more murdered creatures. They then attack Voyager stealing a shield generator and escape, kidnapping Seven of Nine along the way. Voyager, unable to raise shields, suddenly finds itself under attack from the angry nucleogenic creatures.

Seven has encrypted the codes accessing the Equinox warp controls, delaying their plan to murder another 63 aliens for fuel. After learning the Doctor in their sickbay is from Voyager, and erasing his ethical sub-routines as they did with their EMH, they tell him to probe Seven's brain to obtain the codes, despite the fact this may permanently incapacitate her. During his examination, he sings "Oh My Darling, Clementine" with the partially unconscious Seven, much dismaying Ransom as it seems to make his probing go more slowly.

Janeway starts taking the objective of stopping Ransom to extremes when she orders torpedoes to be fired on the Equinox, nearly kills an Equinox crew member during an interrogation, tractor beams an Ankari ship, and relieves Chakotay from command when he questions her orders.

Ransom starts to realize the error of his ways and orders the crew to return the Equinox to Voyager, but the remaining crew, except for Ensign Marla Gilmore, attempt to mutiny against this. With Gilmore's help, Ransom transports part of the crew, as well as the Doctor and Seven, back to Voyager, while the remaining mutineers are killed by the aliens. After transporting Gilmore to Voyager, Ransom stays behind, sacrificing himself to the nucleogenic creatures while moving the ship far enough away from Voyager to protect it from the resulting explosion.

As Voyager resumes its journey home, Janeway reinstates Chakotay to Commander and strips the five surviving Equinox crew members of their ranks while integrating them with Voyagers crew. Seven promises to help the Doctor secure his ethical sub-routines from being deleted in the future.