Fifth Drax

Drax's fifth incarnation posed as Rosser, the butler of his twelfth incarnation during a plot hatched by a previous incarnation of his. With the unwitting help of the Fourth Doctor and Romana II, they raided the most secure safe-house in history. (AUDIO: The Trouble with Drax)

Biography
After the Third Drax gained the map to Altrazar, he and "Rosser" went to the city with the Fourth Doctor in order to retrieve an item. On the city, the Doctor discovered Rosser's real identity, but, by then he and his previous incarnation had already ran away with the item, using the Doctor's TARDIS to get to a rocket.

In the rocket, the Draxes realised they were being chased by Galdron Cabot, the rival of "Rosser"'s boss. From the ship she was stationed on, Romana II was able to communicate with both the Draxes and Cabot, and soon realised that they too were incarnations of the Time Lord.

Upon discovering this, the Doctor and Romana became aware they got involved in a con that involved several of Drax's future incarnations, who needed the Blinovitch Limitation Effect limiter to avoid temporal catastrophe. Needing a fall guy, they conned the Doctor into stealing the limiter, which was what allowed his future incarnations to successfully cooperate on this scheme and others in the first place.

The Doctor and Romana met the four Draxes in the Rutan's Tendril, and called Inspector Fleur McCormick to arrest them. However, by the time they realised that Drax must have known he would have been arrested over different incarnations, they realised the truth about McCormick and her men, and by the time they returned all of Drax's incarnations had escaped in their TARDIS. (AUDIO: The Trouble with Drax)