Orbit
The scientist Egrorian offers Avon a powerful weapon, the Tachyon Funnel, in exchange for Orac. Servalan, who is behind the transfer, prepares a plan to double-cross Avon that would give her both the Tachyon Funnel and Orac.
More from Series 4
Episode 1
Rescue
Dorian, owner of the spaceship Scorpio, rescues the crew from Terminal. He tries to enlist the help of Orac to build a teleport mechanism for Scorpio and attempts to kill the crew.
Episode 2
Power
The Scorpio, rendered inaccessible by an elaborate security system, is stolen by a native of the planet who seeks to escape. Avon completes the Scorpio teleport system with the help of Orac.
Episode 3
Traitor
The planet Helotrix is falling easily to attack from a new Federation pacification drug, as are many other star systems. Tarrant and Dayna teleport down to the surface to investigate. Servalan, deposed of her presidency in the Federation, is back under the alias Commissioner Sleer having wiped all records connecting herself with the identity of Servalan.
Episode 4
Stardrive
After attempts to match the course of an asteroid for cover result in collision with the asteroid and severe damage to Scorpio's engines, the crew search for an experimental stardrive developed by an ex-Federation designer who is now working for a terrorist group.
Episode 5
Animals
Dayna meets an old friend, Justin, to seek help with synthesizing an antidote to the Federation pacification drug. Servalan learns of Scorpio's visit to Justin's planet and of the genetic research he is performing there.
Episode 6
Headhunter
The crew rescue a protege of Ensor's who instead turns out to be his android creation seeking to unite with Orac.
