Hoyle was described as "a red-haired man in his early forties." He had very similar physical features as his Garde, and they may have even grown up in the same region of Lorien, possibly on a Kabarak Colony somewhere, seeing as they chose rural places to stay after landing. When Adamus Sutekh sees footage of Hoyle in London, he says he has a bigger build than he originally thought.
Little is known about Hoyle's personality, but he seemed to be very kind and quiet. He had a peaceful life with his Garde, and was accepting of her constant photography hobby, despite it being very dangerous. Like most Loric, he appeared to be very intelligent, always reading like Maggie. This may have been the reason why she chose to read as well. Hoyle, to the Mogadorians however, appeared as a terrorist, and a violent, trigger-happy criminal.
After landing on Earth, Conrad left for Europe, where they spent most of their time. Several years after settling in, Conrad moved them to the UK. They lived in the Scottish Highlands, where they had set up a safe house. They stayed on a cottage for quite some time, where they even raised a goat.
After a while, the Mogadorians found him and attacked their safe house. However, he had already relocated Maggie to London, and was most likely staying in the Highlands to hide Maggie's Loric Chest. When the Mogs attacked, he fought back violently, and it ended with their cottage burning down.
Later on, he boarded a train to London, where he was secretly trailed by Mogadorians. When he got on a bus, he defended himself and started shooting at them with submachine guns. However, he was ultimately defeated and killed, most likely by warrior Ivanick Shu-Ra.