“Contagion” is episode eleven of season two of Star Trek: The Next Generation.
The Enterprise is heading into the Neutral Zone having received a desperate plea from the captain of their sister ship, the Yamato. A series of malfunctions have been plaguing the ship and hopefully if both crews work together, they will eliminate the problems before their presence is detected by the Romulans.
Captain Picard enters the bridge when they are 4 minutes out. Data says they are downloading the logs and Riker asks him about the odd reading. Picard asks if it’s trouble; they aren’t sure. Worf informs them that the Yamato is coming into range and they are receiving a transmission from Captain Varley.
Captain Varley says the malfunctions are becoming serious; they lost an engineering team when the computer shut down the forcefield in an open shuttle bat. It’s affecting every system simultaneously. Varley and Picard wonder if it’s a design flaw, but at the moment they just need to get the ship fixed. Varley thinks it’s premature to evacuate non-essential personnel to the Enterprise.
Varley had heard rumours from a couple of archaeological digs that made the Iconians seem a lot less like legend. He managed to locate their homeworld, in the Neutral Zone, and couldn’t risk the Romulans locating it. It’s a virtually dead planet but enough technology remains to give the Romulans an unbeatable edge.
The transmission from the Yamato is degrading and Worf reports there is an energy build up in the engineering section. The seals on the antimatter chamber are decaying. The secondary hull explodes and the explosion destroys the severed saucer section. There are no life readings. Evacuation would not have been premature. Then a Romulan ship decloaks.
Both the Romulans, when they respond, and the Enterprise demand that the other explain their illegal presence in the Neutral Zone. The Romulan captain, Taris, states they are not responsible for the destruction of the Yamato. They would not have stopped with one starship. They want the Enterprise to leave at once. Picard isn’t going to leave until he determines what happened to the Yamato. The Romulans ship cloaks, which means they can’t fire. Unless, Worf suggests, they have overcome that flaw.
Geordi briefs the senior staff on what happened to the Yamato; the seals between the matter and antimatter chambers degraded. Not impossible but highly improbable requiring a specific series of events. The Yamato destroyed itself. Picard wants Geordi to check that it isn’t a design flaw. Until they know that, withdrawing isn’t an option.
The captain views Varley’s personal log looking for entries on the Iconians. Varley explains how he tracked down the planet and found advanced technology, as well as spotting, then losing, a Romulan cruiser. They were scanned by an Iconian probe but wound up unable to explore the planet thanks to the problems. Varley will contact the Enterprise and hopefully convince them to help and continue the mission. When the captain leaves his ready room, the door doesn’t immediately work.
On the bridge, Data brings up the log entry of the Iconian probe scanning the Yamato. According to Geordi, everything is checking out in engineering, so Picard wants to head to Iconia. It’s close to the Romulan side of the Neutral Zone. Picard hopes to prevent a war, rather than cause one.
Wesley wants to speak to the captain, initially about the Iconians, who he thought were a myth. No; they had at least several colonies and may have been warlike. They are rumoured to have travelled without starships, appearing out of thin air. What Wesley really wants to talk about is the Yamato. How do they handle its destruction so easily. Not easily; they handle it because they are trained to, as Wesley will. The captain orders the replicator to make him a cup of Earl Grey. And gets a plant.
The Enterprise is also suffering from system failures that are so far random. According to Geordi, the Yamato‘s destruction was not a design flaw. The alien probe may be responsible but he needs to see it. The Enterprise‘s problems will get serious.
Iconia is devoid of life and its major cities have been heavily damaged from large scale orbital bombardment about 200,000 years ago. There is an energy source and a projectile, matching the probe, is launched. The captain orders the probe be captured but Geordi realises this is a bad idea. Comms are down and the turbolift throws him around before he arrives on the bridge and says to destroy the probe. If it scanned them, there would be no chance to save the ship.
The Enterprise‘s problems are getting worse and eventually it, too, will be destroyed until this is fixed. The Romulans are still out there as well.