The bio data extract is a detailed description of the Doctor's molecular structure - and this information, in the wrong hands, could be exploited with disastrous effect.

The Gallifreyan High Council believe that anti-matter will be infiltrated into the universe as a result of the theft. In order to render the information useless, they decide the Doctor must die ...
 

On his return to Gallifrey, the Doctor learns that his bio data extract has been stolen from the Time Lords' master computer, the Matrix. The Gallifreyan High Council believes that anti-matter will be infiltrated into the universe as a result of the theft. The information must be rendered useless - the Doctor must die.

First broadcast in1983, this is the first story since The Three Doctors to feature Omega, a bitter Gallifreyan exiled forever from this Universe. This novelization by Terrance Dicks was adapted from the original script by Johnny Byrne.
 

Shielded by a collapsed star lurks a malevolent presence, an alien consisting of pure anti-matter. Its intention? To bond with a Time Lord and so cross over into this dimension through the Arc of Infinity - the gateway to all dimensions.

Suddenly, the Doctor finds himself under attack and the TARDIS recalled to Gallifrey where he is put under sentence of death by the High Council of Timelords, For the bonding must be prevented at all costs.

Once there, the mystery deepens. How could the alien have gained the vital biodata extract necessary to carry out the bonding? Is there a traitor amidst the Timelords? What is the link between the alien and Tegan's cousin's disappearance in Amsterdam? Just what is the identity of the shadowy alien - have he and the Doctor met before?

The Doctor must find the answers - and quickly. It is not just his life at risk. If the bonding is completed, it could cause the collision of matter and anti-matter and the destruction of all dimensions ...

Originally transmitted 3 -12 January 1983, this 4 part adventure sees Colin Baker's first ever appearance in the program as Time Lord Security Commander Maxil and the return of the Doctor's old enemy Omega, whom he originally encountered in The Three Doctors.

Running Time: 98 mins approx
Produced by John Nathan-Turner
Directed by Ron Jones
Cover Illustration by Pete Wallbank