“Slither” is episode twenty-three (originally shown as episode twenty-two) of season three of Sliders.
At an airport, a customs agent wants to look inside some boxes that a woman is having loaded onto a small plane. She says that opening the boxes will allow oxygen to damage the bones. The law may be the law, but she suggests changing it to the thank you law. And offers a bribe. He accepts. When he’s gone, one of the boxes of ‘bones’ hisses and the woman tells those loading them that the thank you law applies to them too.
Rembrandt finds Quinn inside the terminal; Quinn tells him they got bumped. Yes, they had tickets, but so did the other 60 people for a 20-seat plane. They’re on vacation, having left Maggie and Wade in San Francisco. The next flight back is in over a week, which is after they slide. The customs official from earlier is asked if he knows of any charter flights. Just one, leaving today. The two head to the plane, where the woman, Kyra, isn’t interested in giving them a lift. Then vehicles and people with guns arrive and start shooting. Quinn and Rembrandt help load one of the boxes on and the plane leaves.
Kyra tells them she’s a freelancer who is transporting a mated pair of very rare snakes to a biotech farm; they could have the cure for Parkinson’s. Quinn and Kyra are flirting. The lock on one of the boxes was damaged by a bullet, and the snake gets out. It gets into the cockpit and throttles the pilot. Quinn tries to bring the plane up but fails.
Wade finds Maggie; the guys got on a charter flight but there was a shootout. And the plane is heading somewhere they can’t get to, where LA would normally be but in this world it’s drug country. They look for a charter themselves; the pilot is convinced to just rent the plane, for $300. But says fuel is extra. He’s open to on-cash offers. Maggie knees him in the groin.
Quinn is trying to repair the radio at the crash site. He gets it working and reports that there are three survivors before it shorts out. The escaped snake is watching them. Kyra comes around; she’s told they only have one snake. Rembrandt is perfectly willing to abandon the other, but he says it’s up to Quinn. They take the other container and head to the nearest town, about 10 miles away.
Wade and Maggie have landed at the others’ intended destination. A man, Carlos, says it went down and a friend of his was on it too. The owner got a distress call from someone named Mallory. Maggie wants to fly over, but Carlos says that the cartels will shoot down unfamiliar aircraft. They can ride with him; he has a truck full of supplies. A man enters and greets Carlos. Carlos suggests Wade and Maggie wait in the truck. It looks like the newcomer, Don, is dangerous, but it turns out that Carlos is the dangerous one. He accuses Don and Kyra of trying to cut him out of the deal and stabs Don.
The others are in the jungle; the snake is following. They walk out into a field and Kyra warns them that those are tobacco plants. The cartels have people patrolling. Tobacco is illegal on this world. Kyra walks into a tripwire which sends flares up, and alerts two men with guns. Rembrandt wants to dump the snake, but once again, it’s up to Quinn. Them not being TEA doesn’t stop the guards from shooting. They split up and the guards do too. Quinn manages to knock one down and take his gun. The snake drops on the other and kills him. Rembrandt sees and would like to shoot the snake. Kyra tells him it’s an endangered species. It’s also too aggressive to currently try to catch.
Quinn is tired of being the one making the decisions; he’s feeling the loss of the professor strongly. He is attracted to Kyra; Maggie to Carlos. Neither looks to have chosen well. Those in the jungle are being followed by the snake, and many others, which isn’t normal, and Maggie and Wade are still clashing.