Capt. Matthew Gideon assembles the crew that will be with him on the experimental starship Excalibur. Their mission: explore the reaches of space to find a cure for the deadly Drakh virus that will overrun Earth in five years.
The Excalibur goes to Babylon 5 so that Gideon can meet with an ambassador for permission to go to a planet that might have technology that can help Earth. But the ambassador refuses and Gideon is not going to accept it. And Ellerson runs into his ex-wife, who is in trouble with a loan shark. When he pays him off, he feels she owes him more. Anf goes to great lengths to collect.
The Excalibur picks up a Senator who comes on board with a guy. He then instructs them to go to Earth but doesn't tell them why. Along the way they pick up a distress call from Lochley who is trapped in space. They pick her up over the Senator's objections. When they reach Earth a vessel comes out of Earth and explodes and a life pod comes out. The Senator tells them to bring it on board. And when they do, they discover that an experiment is being planned to take place on the ship.