In the North Atlantic, Mulder and Scully investigate the crew of a US Navy Ship, all of whom somehow radically aged. The agents locate the ship but, like the vessel's crew before them, Mulder and Scully also suffer from rapid aging.
The show begins with a naval ship evacuation taking place in the Norwegian Sea. Captain Barclay tells the men, who are preparing to leave, that they are committing mutiny. Lt. Harper says he will not wait for help, and that it may already be too late. Cpt. Barclay levels a gun on him, but then lets everyone go. They leave Barclay behind on the ship.
Eighteen hours later, a fishing vessel, with a crew paying cards, detects a drifting boat. They radio out a call to the drifting craft but get no response. From the deck, they spy a boat full of huddled men. They throw out a rope to reel them in. We see some weak hands holding tight to it. The fisherman call out only to find upon closer inspection the entire boat is filled with the naval crew, only much weaker and decrepit.
At Bethesda Naval Hospital, Mulder and Scully meet and speak about a missing Navy ship, that has been gone forty-two hours. According to Mulder, a Canadian troller picked up the only eighteen survivors, and now only one is left alive in the Intensive Care Unit. Mulder asks Scully to inspect the survivor and report back. Upon seeing the older Harper, Scully asks if there has been a mistake. A doctor questions Scully's credentials and clearance, and then asks her to leave before Scully can learn anything. Scully and Mulder discuss what she saw and then go over the route which the Navy ship took. Mulder says nine ships have disappeared in roughly the same place along the 65th parallel. Scully wonders if it is like a Bermuda Triangle of sorts. Mulder calls it a wrinkle in time. They discuss a 'Philadelphia Experiment', which was discontinued in light of the Manhattan Project. Mulder tells her about a ship which disappeared without explanation from the Philadelphia ship yard and reappeared in Norfolk, Virginia. It may have done so with the help of alien technology and the manipulation of wormholes of earth. The two then take off without telling Skinner they are investigating this space-time phenomena.
In the port of Tildeskan, Norway, at a shipyard bar, Mulder and Scully look over a map with a Norwegian man. It becomes apparent that no one so far is willing to take them out to where the ship disappeared. Many of the sailors in the bar give them wry looks. Scully thinks they look afraid of their undertaking. A man comes out of the shadows and explains why the men will not take them on: ships must get a certain classification before they can go out into those kinds of waters. Enter Henry Trondheim; he recommends his ship to take them out. Trondheim says the trip will be ten hours each way. Scully wonders why everyone is so afraid and Henry tells them it is because of various mythologies. When Henry asks about the nature of their visit, Mulder gives a vague answer. Henry says he will take them for a price.
Aboard the ship, Mulder looks to be sea sick. When asked why the journey is taking longer than expected, Trondheim says he has never seen the fog this thick and it is making travel difficult. Besides, Trondheim notes, they are right where they want to be. The naval ship just appeared on his radar mysteriously. As a matter of face, all of his instruments are behaving oddly. The ship appears so fast in their sight that they cannot slow down in time, causing their boat to strike it at full speed, and bounce off.
Mulder and Scully climb aboard the naval ship, which Trondheim calls a ghost ship. Everything is rotted and rusted over, including the plaque saying it was built in 1991. The entire vessel appears to be abandoned and old. They go to inspect the crew quarters and the plaque mysteriously develops another layer of sediment. In the quarters, they find several decaying bodies, which appear as though they have been dead for a long period of time. Scully tries to take a sample of some residue on a dead man's hand, but the hand snaps off. Scully and Mulder hear a noise, which turns out to be Trondheim's ship starting and leaving without them. It disappears into the fog.
Mulder and Scully work to get the ship running again, but it is covered in the same residue. Any work on it is impossible; and the radio is inoperable, as are the engine parts. Trondheim demands straight answers. Mulder tells him it might be the result of a government experiment, in which time might be manipulated. Suddenly, Halverson can be heard yelling from the depths of the ship. Upon discovering his head has been smashed in and is now dead, the trio hear someone moving through the ship. They go to investigate. In the galley freezer, they find Cpt. Barclay hiding with a bottle of Jack Daniels. He is aged horribly and frail.
Scully interrogates him and asks about a light the crew saw. Barclay says they had power loss after that; even the sea and the wind stopped. Trondheim thinks Barclay a drunkard. Barclay differs, saying time got lost for him and all his men. In a private conversation, Mulder and Scully do not think Barclay could have killed Halverson, because Barclay is so weak. In the meantime, Trondheim commits Halverson's body to the sea, and is then attacked by Olafsson. Mulder stops the fight with Olafsson, whom he believes to be important because he has not aged. Trondheim despises him because he is a pirate and a deceiver, whose friends might have taken his boat just now.
Barclay dies suddenly. Scully says he is turning into a pillar of salt. Mulder tells them to tie up Olafsson so they can get some rest. After a quick nap, Mulder and Scully begin to show signs of rapid aging. They all have—except Olafsson. They argue about what the phenomena is and who is to blame. Scully claims oxidation of cells and tissues may be caused by the very water around them, and a large metallic object could be imposing on them free radicals. The ship begins to ooze rust. Trondheim is left with Olafsson while Mulder and Scully poke around the ship. Olafsson tries to bargain with Trondheim to let him go. Mulder identifies the one pipe which has not rusted over and finds it leads to sewage processing. They find a spot where they believe Olafsson and his friends were hiding and determine the only worthy drinking water comes from there. We return to Trondheim to see he has killed Olafsson and is now drinking water from a toilet.
Mulder is not happy that Olafsson is missing. He and Trondheim argue. Scully asks for blood and urine samples. After testing, Scully finds awesome amounts of salt, which is causing rapid cellular damage. Mulder does not look to be doing so well as compared to Scully and Trondheim. Trondheim wants to stop giving him rations of water. Trondheim takes to roaming the ship one night. Scully finds he is hoarding all the clean water to himself. A standoff takes place and Trondheim locks her out of the sewage hold. Scully rummages through all the crew lockers and finds a snowglobe. Next, she tears apart the kitchen and finds a can of sardines. She combines all the moisture in the entire ship and gives it to Mulder. He tells her to have it instead because as a woman she can retain water better. He will wait for rescue. The ship begins to rock violently and the concoction is lost. Mulder thinks the ship is taking on water, as the hull has finally corroded through. We then see Trondheim taking on a lot of water in the hold. He cannot get the door open and drowns.
Fourteen hours later, Mulder jokes he always wanted to take a cruise when he got older. The service is terrible on this ship, he says. Scully speaks about her coma experience. She say they have nothing to fear when they die. She writes in her journal that Mulder has lost consciousness and the ship must sinking for sure. Among Halverson's belongings, she found a children's book of Norse mythology depicting the end of the world, and begins to concede that she may die.
A rescue crew is seen boarding the ship and finding Scully and Mulder together. Scully awakens under the care of the same doctor who threw her out at the beginning of the episode. The doctor tells her they were only able to save Mulder because of her notes about the conditions, and that the ship sunk an hour after they were rescued, so it may no longer be examined.
- The actors who played the Norwegian fishermen spoke a mix of Danish and Norwegian, with Finnish pronunciation for some words.
- When Mulder shows Scully the map of Europe, he tells her a ship left from Leeds and disappeared near Norway. This may not be true, as Leeds is a land-locked city in England. However, the River Aire does flow directly through the heart of Leeds and empties into the River Ouse, which then empties into the River Trent, which leads to the North Sea. This makes for an unlikely but possible route to the sea.
- The US première of this episode helped the Fox network secure its highest ever Friday night rating, confirming the status of The X-Files as one of the USA's top-rated television shows. (The X-Files Magazine Volume 1, Issue 2, p. 27; The X-Files Magazine Volume 1, Issue 4, p. 28)