Gideon and Lochley must prevent a doomsday cult from killing everyone at a virus conference on Mars.

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.

In an attempt to understand the nature of the Drakh virus better, the Excalibur is sent back to Earth's orbit for a top-secret special pick up. Familiar face returns. The show ends on an open ending.

The Making of Crusade - a behind-the-scenes featurette

Forging Excalibur - learn about the starship from the inside out