- You may be looking for Kalinda Ulrik.
Ulrik was a Jariden colonel, ident number 6-Four-Alpha-Z, who met the Doctor in four incarnations: his Fifth, Sixth, Seventh and Eighth selves. He served in the 47th Division of the Jariden Army. He was the brother of Professor Kalinda Ulrik. He headed a security inspection of the Vault of Stellar Curios. He invited the Daleks to the Vault. He was a functional upgrade of the Jaridens who fought in the Battle of Pejorica, incorporating technology unknown to the Daleks.
He fell back in time and met Michael Faraday and the Seventh Doctor. He located a time corridor and travelled to the Battle of Pejorica, where he met the Sixth Doctor and realised that he, the Dalek Prime and a Special Weapons Dalek were travelling back along the Doctor's timeline. Although he initially wanted to give the Daleks the Jariden device to avert loss of life, he ultimately sacrificed himself to stop them taking it once he returned to the Vault of Stellar Curios, and was killed by the Dalek Prime. (AUDIO: The Four Doctors)