The Quintesson known as Inquirata was stationed on the planet Aquatron as an "ambassador". He operated from inside an exo-body that disguised his true nature and provided him an appearance resembling the Aquatronian natives conquered by the Quintessons. A master of brainwashing and hypnotic conditioning, Inquirata maintained control of the Aquatronian civilians and the Sharkticon shock troopers as part of his duties.
The Quintessons had long chaffed at their defeat and exile from Cybertron millions of years ago, and Inquirata was part of a plot to gain vengeance. In an effort to reverse engineer the Autobot Matrix, Inquirata created a less-impressive copy known as the Sharkticon Matrix. With its similar code, Inquirata was able to interface remotely with the true Matrix inside Optimus Prime's chest. It sent out a siren call that lured the Autobot leader and his Ark to Aquatron, while also subliminally causing Optimus to doubt himself and the Matrix.
While the Autobots were en route, Inquirata also tapped the datatracks of Shockwave back on Cybertron. The Decepticon regent had plans to hack Vector Sigma using the power of the last Prime, Alpha Trion, but Inquirata established a backdoor into Shockwave's systems to use that same power to reactivate the long-dormant Space bridge, allowing the Quintessons' conquering army to return to Cybertron when they were ready.
As the Autobots arrived on Aquatron, Inquirata slipped into his role as the friendly and slightly awkward Curator of Aquatron, welcoming the Autobots with open arms. The Curator explained that, while Aquatron was not directly related to Cybertron or its colonies, it did enjoy a trade relationship with Cybertron during the lost Golden Age. They were cut off after the Space Bridge eventually fell into disrepair, but had continued farming large quantities of energon for trade with other cultures. The Curator claimed the Aquatronians were eager to resume trade negotiations with such honored guests.
Inquirata arranged for his false Matrix to trigger a seizure in Optimus Prime, prompting the Autobot leader being transported to the nearest medical facility. There Doctor Xeros performed an examination of Optimus. Although Jazz and medical officer Ratchetwatched him too closely for Xeros to examine the Matrix directly, his scans did fully analyze Optimus and his connection to the Matrix, to the Quintessons' benefit. Meanwhile, a group of three Autobots (Rodimus, Kup and Bumblebee) had become suspicious of the Aquatronians and infiltrated one of their underwater cities. When they found the dormant Sharkticon army, they were incapacitated by the hypnotic Hydratron. The Curator then used aggressive reprogramming to alter their memories and send them back to the Autobots without any recollection of the encounter.
When the Decepticons arrived in pursuit of the Autobots, the Curator dropped all pretense of bumbling host and incapacitated both the Ark and Nemesis using space-based weaponry. He then revealed Aquatron's connection to the Quintessons and "politely" forced the Autobots and Decepticons into peace talks. The night before the talks were scheduled to begin at the Quintessons' sacred Hall of Justice, he also secretly met with Optimus, Megatron, and Starscream, keeping them off-balance and turning them against each other. Indeed, Megatron brought a squad of Vehicons to attack Prime when they met alone for the negotiations, and Starscream used Skywarp to set a bomb underneath the same venue, hoping to eliminate the Prime and "mighty Megatron" at the same time.
All this played right into Inquirata's hands, as he then accused the Cybertronians of blasphemy for defiling the sacred hall and other trumped up charges in a kangaroo court before the Quintesson ruling body. The Cybertronians were condemned by their own actions and by brainwashed testimony compelled from the bomber Skywarp and the Autobot trio from earlier. The Cybertronians were pronounced "innocent" and sentenced to death by Piranacon. Optimus Prime had earlier discovered the Matrix's corrupted influence on him and turned the device off. To force him into a situation where he would reverse the action, the Curator ordered Optimus and Megatron's death sentence would be through trial by combat. Indeed, Optimus was forced to reactivate the Matrix in order to survive his battle with Megatron, inadvertently feeding energy into the Quintessons' collectors to power the Space bridge Shockwave unwittingly reactivated for them on Cybertron.
Inquirata released the mighty general Tyrannicon from stasis, and he led the invasion of Cybertron. However, Optimus and Megatron escaped their death at each other's hands and worked together to locate the Curator's inner sanctum. Megatron acquired the Sharkticon Matrix for himself, removing control of these troops from Inquirata and Tyrannicon. The Curator was forced to fight back against his own shock troopers sent to murder him, and so he activated the power of the Hydratron. In the end, however, it was General Tyrannicon, battered and bruised from losing his armies on Cybertron, who finished the Curator. He believed Inquirata had deliberately turned the Sharkticons against him, and took his revenge.