Mat Irvine
Mat Irvine was the visual effects designer for the Doctor Who television stories The Face of Evil, The Stones of Blood, The Creature from the Pit, Warriors' Gate, Warriors of the Deep and the K9 and Company television story A Girl's Best Friend. He also doubled for actor Vincent Pickering when Pickering's character Sagan was electrocuted in Warriors' Gate. (DWM 315)
Though primarily associated with the later Tom Baker era, he was also the uncredited operator of the K9 Mark IV in School Reunion (DCOM: School Reunion).
Irvine also worked on Blake's 7 and wrote the book Doctor Who Special Effects. He also contributed to the charity reference book Behind the Sofa: Celebrity Memories of Doctor Who.