Damon Larkham, also known as the Demon, is the leader of IG-88.
A former leader of a British Special Forces unit, Larkham was called into question during an investigation into Trevor Barnaby, and was arrested. However during a transfer, Larkham escaped.
Larkham soon became a bounty hunter, and created a group of bounty hunters, the Intercontinental Guard, Unit 88. His work as a bounty hunter led to his nickname, the Demon, and soon he became renowned as the world's number one bounty hunter.
At an unknown time, the Demon recieved extreme burns to his head, resulting in scars on his face and melting most of his ears into his head.
When a bounty was set for fifteen targets, whose heads needed to be taken to a castle in France for verification, Demon led IG-88 to claim as many of them as possible. They learned that a number of targets would be gathered at the Karpalov coalmine, as well as Elizabeth Gant, the girlfriend of another target, Shane Schofield.
Demon and IG-88 infiltrated the mine, emerging from behind the terrorists, forcing mosty of them to flee from their attackers into no-mand's-land. After he and other members of IG-88 killed Nigel Kingsgate and Iman Khalif and took their heads, Demon came across Gant, and he had her knocked out with the intention of using her as bait for Schofield. Cowboy reported to Demon that he had taken Hassan Zawahiri's head, but that William Ashcroft's had already been taken by the Skorpions. Demon was satisfied enough with their haul that he ordered his men to depart, and as they did, they managed to capture General Weitzman alive.
IG-88 relocated to a British airbase in Kunduz, where Demon gave Weitzman to a pair of MI6 agents who wanted to interogate him before they let IG-88 kill him. Demon then sent Cowboy with the heads they'd collected to go to the castle to claim the bounties, while Demon himself took a squad to go to London to take the Mossad agent Benjamin Rosenthal.
After arriving at Canary Wharf, Demon's strike force assaulted the Mossad's offices at King's Tower, taking out several Mossad personnel in their search for Rosenthal. They encountered some resistance in a pair of Marines trying to find Rosenthal themselves, and soon Demon had their Lynx helicopters strafe the tower. Though they lost several men and one of the choppers, IG-88 was able to kill Rosenthal and take his head.
Soon the bounty was claimed for Rosenthal's head, at which point Demon discovered the Black Knight had killed his bounty-retrieval team and taken the heads he had collected from Afghanistan.
Soon afterwards, Demon and IG-88 tracked down either Schofield or Simon Zemir down to the Kormoran ship Talbot, where they opened fire on Zemir's protection squad as he tried to disarm the Chameleon missiles. However, Dmitri Zamanov and his remaining two Skorpions used IG-88's attack as a distraction as they took Zemir's head. As the Sayaret Tzanhim lost formation, Demon and his men decimated them before realising Zamanov had fled with their prize. They soon caught up to the Skorpions and took Zemir's head after killing Zamanov's men. Demon then spotted Schofield and had his men open fire, however in the chaos caused by another freighter's impact, Demon decided to try and seal the hatches to force Schofield to come to them, however the Talbot sank and Schofield escaped another way.
Once the hunt was over, Demon learned the identity of Knight's employer, Lillian Mattencourt, and IG-88 arranged a car bomb to detonate once she was done meeting with Knight. Though annoyed at losing three heads to Knight, the Demon noted that such was simply part of the nature of their occupation, and with Knight's payment now up in smoke, told his fellow bounty hunter that he considered the debt settled and that they would see each other again.
- Demon (having a disfigurement or odd feature like some of Reilly's other villains) has a severely scarred face/head, which has also melted his earlobes off.
- Demon is one of only two prominent villains in the Scarecrow series (the other being Marius Calderon), to still be alive, although Demon is not a main antagonist like Calderon.