Rorvik

Rorvik was the captain of a privateer ship and a slave trader who transported the time sensitive Tharils.

Rorvik used a Tharil, Biroc, as his navigator, since only time sensitives could navigate the time winds. Instead, however, Biroc took Rorvik's ship to the Zero Point between E-Space and N-Space and then escaped, leaving the ship stranded.

Exploring the void of the Zero Point with two of his crew, Packard and Lane, Rorvik discovered the Doctor's TARDIS and took Romana II prisoner, suspecting she was also time sensitive and could replace Biroc as navigator. When she proved inadequate, he headed to the Gateway with most of his crew, instructing Aldo and Royce to carry out the dangerous procedure of reviving the Tharils onboard the ship without the proper equipment.

At the Gateway, Rorvik encountered the Fourth Doctor and K9 who were in the process of interrogating a Gundan. After the Doctor managed to travel through the Gateway, Rorvik became convinced he could use it to return to N-Space and tried to force his way through, in the end bringing in the dangerous MZ laser. He captured the Doctor and Romana when the time winds carried them back to the Gateway. There it was realised that the super dense dwarf star alloy Rorvik's ship was constructed from, the only material that could hold Tharils, was causing the Gateway to collapse. Adric then briefly managed to gain control of the MZ and force Rorvik to free his friends.

With the MZ having failed, Rorvik decided to use an exhaust blast from his ship on the Gateway. He ordered Sagan to begin reviving the Tharils, even though the process would be fatal to most of them, in order to gain a new navigator. He failed to realise the back-blast would simply accelerate the collapse. He fought with the Doctor as he and Romana tried to drain the power from the engines. After the Tharils were freed and taken to safety by Lazlo, the Doctor and Romana fled with Biroc. Rorvik then triggered the back-blast and caused the Gateway to collapse, destroying his ship, his crew and himself. (TV: Warriors' Gate)

Behind the Scenes
Robert Hardy, Derek Jacobi, Stratford Johns, John Normington and Frank Windsor were all considered for the role before Clifford Rose was cast.