Arcee is a cybertronian and a member of the Autobot faction.

Most make the mistake of noticing only Arcee's gender, but these first impressions are quickly expanded upon. Sure, she's pink, but she'll have swords down on you by the time you remember that's just the color of Transformer blood. Arcee is a ruthless and deadly warrior who's an expert in hand-to-hand combat and one of the best sharpshooters on record. The reason for her ferocity is how much she cares for her fellow Autobots and especially the humans they protect. She knows how fragile her organic companions are, and she's equally aware of the evils of which the Decepticons are capable. Peers such as Hot Rod and Springer may be more durable than the humans, but she no less fights to defend them as well. They get in plenty of trouble, so someone has to keep their wits about them to pull them out of the fire when they get in over their heads.

A close associate of Hot Rod and Springer, Arcee fought in both the Battle of Autobot City and the Unicron War in 2005. Following that, she continued working closely with Rodimus Prime as one of his primary warriors. In 2006, she binary bonded with Daniel Witwicky to save his life, becoming a Headmaster.

During the assault on Autobot City, Arcee was instrumental in helping Springer transform the fortress to repel the Decepticon invaders, buying precious time for reinforcements and likely saving many lives. She was among the few Autobots to survive Megatron's savage blitz on the city and to form the small army sent to engage the planet eater, Unicron, who was threatening Cybertron at the time. Although she was nearly left behind when Unicron's minion Galvatron attacked, she, along with Autobot leader Ultra Magnus, and his small attack force managed to hold their own against the villain long enough to befriend the citizens of the planet Junk, reunite with their lost Autobot comrades, and fight their way into the depths of Unicron where Hot Rod was finally able to open the power of the Matrix and kill the giant foe.

Throughout the entire affair, one of Arcee's top priorities was the protection and care of young Daniel Witwicky, a human friend of Hot Rod who had wound up on the adventure with her.

After the Matrix chose Hot Rod to become the new leader of the Autobots, Rodimus Prime, Arcee remained as one of his closest soldiers. She helped fight a surprise attack on the first Galactic Olympics. When Ultra Magnus, Kup, and Spike Witwicky were discovered missing, she and Springer took off after the perceived kidnapper. Although they were successful in capturing their quarry, the Skuxxoid, and taking his ship, he deceived them about the identity of his employer. Five Faces of Darkness, Part 1 This still turned out to be beneficial as they arrived in time to save Rodimus Prime and Grimlock from being pummeled by a mob of Decepticons. When Rodimus learned that the Quintessons were the real ones behind the kidnapping, she partook in the rescue mission on Quintessa, saving Magnus, Kup and Spike seconds before the planet was detonated.

She, along with the others, was sent by the explosion to the planet of Goo Number 8739-B where they were stranded until the Junkions were called in to salvage them. Five Faces of Darkness, It was assumed she returned to Cybertron with the others, and fought when Galvatron waged a full-scale assault on the planet.

Arcee was among the small group of Autobots that managed to stop a Quintesson plot to use the resurrected body of Optimus Prime as a sort of sleeper agent to lure the rest of the Autobots into a trap. Dark Awakening She was also seen among the other Autobots cheering when Unicron's plan to connect himself to Cybertron failed.

Later she accompanied a squad sent after Galvatron and his troops who had broken into a secret chamber on Cybertron. This too would turn out to be a Quintesson trap. This time, the Decepticons were fooled into releasing the Quintessons’ dangerous experiments, the Trans-Organics, and their most powerful member The Dweller, a giant energy leech that turned all Transformers into energy vampires. After trying to fight off both Galvatron and the Dweller in the dark tunnels, only she and Ultra Magnus were able to escape and warn Rodimus Prime and Perceptor in time to stop the Dweller and turn the other Transformers back to normal.

She, along with Rodimus Prime, Ultra Magnus, and Springer became the targets of crime lord Victor Drath after busting one too many of his operations. With the help of Old Snake, the four Autobots were captured. Their minds were transferred from their bodies into the forms of synthoid humans. They managed to escape disposal by Drath's men, and Arcee eventually made it back to Autobot City in an attempt to warn their comrades that their former bodies were going to be used to blow up the city. Being an unrecognizable human, no one believed her, and she was locked in a detention cell instead. Luckily when Ultra Magnus and Springer managed to foil Drath's plan all four Autobots were subsequently returned to their rightful bodies.

The almost maternal connection between Daniel and Arcee was a powerful one, which was only strengthened some time later when Galvatron tried his most ambitious plan. Using the Key to the Plasma Energy Chamber, Galvatron tried to release its destructive power. Arcee, along with Hot Rod, Kup, and a large Autobot crew, managed to snatch the key away and escaped to the far off planet of Nebulos. There, they became embroiled in the Nebulons' struggle for freedom against their own oppressors, the Hive. In an effort to combat both the Hive and the Decepticons that had tracked them down, the Autobots and the Nebulons agreed to become partners and developed the Headmaster and Targetmaster processes. Having been critically injured trying to save her from Snapdragon, Arcee chose Daniel to partner with as he now needed an exosuit to survive and was her "dearest friend".