While carrying a prototype weapon, the Harbinger was shot down by the Autobots in orbit over Earth. Cut in half by the battle, the bow landed in a forest and was covered up in time. The stern landed in a canyon and was noticeably not buried. When the Nemesis arrived on Earth, Starscream scouted both parts of the ship, but found nothing of interest and left. However, he did not log the Harbinger's location in the computers.
After Airachnid informed Megatron that the Harbinger was carrying the Immobilizer prototype, Starscream took Airachnid to the bow section, where Airachnid accessed the ship's computer systems. This in turn alerted the Autobots to their actions, resulting in Team Prime heading to investigate. Starscream was then forced to tell Airachnid where the stern section was after being webbed up. Airachnid then made her way to the crash site, and managed to find the Immobilizer, only to lose it in a fight with the Autobots. Many months later, Starscream returned to the Harbinger in search of energon. Instead he found a laboratory containing protoforms and cloning equipment, which he used to create five clones of himself.
Starscream later used one of his clone's T-cog to try to restore his missing one. He almost did until he was interrupted when the ship picked up Decepticon energy signatures going around the globe at the same time. Triangulation As well as using the ship's sensors to scan for stuff, Starscream was also able to use it to surf the Internet and look for leads.
Following the destruction of the Autobot base, Bumblebee and Raf Esquivel had the idea of using the resources in the Harbinger. Though they were initially unable to fire the systems up, Ratchet arrived to take over. Ratchet succeeded in getting the systems working, and was able to use the communications to contact Fowler.
The Autobots used the Harbinger's GroundBridge to decoy the Decepticons into spreading their forces thin across the continent. Their deception was quickly realized, but by then the damage was already done. Megatron was enraged by Starscream's allowing the ship to fall into Autobot hands, to which the Air Commander responded by commanding a Seeker squadron to destroy the wreck. However, the mission was aborted early when the Autobots attacked Darkmount, leaving the Harbinger intact.The Autobots salvaged the ship's Groundbridge for their new base.
- The Harbinger appears to be of a similar class of ship as the Nemesis.