Dr Robin Turner
Robin was part of a previous present-day Time Agency branch in 2009, before his team were slaughtered whilst he was out investigating an alien chickenpox. The CCTV evidence suggested it was none other than the infamous assassin Agent Mortis.
It was therefore one of the main influences that made Robin join Agent Liam's team. However, when he discovered that Mortis was to become a new addition to the gang, he left, infuriated.
Upon his return, he threatened Mortis, contrary to Liam's assurance that it might not have been the assassin, but a duplicate, or a clone.
Whilst undercover in UNIT, Mortis hacked into the CCTV footage to reveal that it was in fact the Black Flower Alien Leader who had slaughtered Robin's team, thus removing the bitterness felt between the two.
Robin later found out that Zoey, a member of his old branch, and an old love interest, had also survived. However, his joy didn't last long. Zoey was kidnapped and converted into a Flower Alien, meaning when Robin finally found her, it was too late. He shot the "love of his life" to put her out of her pain, an event which is seen to visibly scar him.
By the end of the events of Judgement Day, Mortis and Robin part their ways. Robin leaves Dartchester due to too having happened. He has gone to see the world, leaving Mortis to start a brand new team...
"The Flower Aliens have taken the only girl I've ever loved away from me, and I need to get her back!"