During his hunt for the Mini-Cons, Starscream hired Shadelock and his crew to assist him. Arriving on Earth, Shadelock informed Starscream that he had found "one of them" as he watched a battle between some Autobots and another Decepticon over Tricerashot. Starscream instructed him to keep watching, in the hopes that he would lead them to the other Mini-Cons.
Shadelock and his team followed Starscream when he confronted the Scavengers, as he believed them to have the Mini-Cons he desired. Unfortunately, said Mini-Cons had already abandoned them before they arrived. The mission wasn't a total bust, however, as the Scavengers had managed to get their hands on the Dark Star Saber, which Starscream took for himself. After Starscream noted how powerful the Saber was, Shadelock insisted that he just pay them and get on with his plan. Starscream, however, declined, claiming that there was no such thing as "too much power".
Shadelock tracked the Mini-Cons to a scrapyard, however the particular Mini-Cons Starscream was looking for had managed to evade them again, causing Shadelock to kidnap the wrong ones-Fixit, Jetstorm, and Slipstream-and get chastised by his client. However, the revelation from Fixit that Starscream's old enemy Bumblebee was on Earth as well was enough to change his tune.
When Bumblebee escaped from the bridge, Shadelock and his crew prevented him from leaving the ship, with Shadelock himself stunning the prisoner after a brief fight. They flanked Bumblebee on the bridge of the ship as Starscream related how he had escaped the Predacons on Cybertron.
Shadelock operated the tractor beam which snatched up the Mini-Cons, and therefore bore Starscream's ire when it turned out they had only captured six of the seven. He and his men guarded the Mini-Cons while Starscream searched for the seventh, and threatened to terminate them when Bumblebee again broke free. When the other Autobots arrived, the battle spilled outside, until the combatants were all rendered unconscious by Starscream using the Dark Star Saber. When Shadelock and his men came around, they saw Starscream and Optimus Prime dueling, and opted to forget getting paid. Their escape was thwarted by the rest of Team Bee, and they were later secured aboard Prime Force One for transport.