A Replicant was an advanced automaton of Jaridian design and were formed from Probes.

The Jaridians were the developers of the technology that created both the Replicants and the probe devices that made their highly advanced infiltrators. Due to their lack of interdimensional drive technology, the Jaridian Imperium deployed their probes in a similar fashion as land mines and were sent millions of years ago into deep space with the intention of finding their creators enemies, the Taelon's and destroying them. Thus, they spent countless years drifting through the cosmos and falling on worlds where they sought out any form of Taelon presence whereupon they reacted by generating Replicants that sought out and exterminated their Jaridian's ancient enemy. (Episode The First of its Kind)

One such probe later landed on the planet Earth at the Amish town of Paradise where it remained in its inactive state. It began replicating butterlies and used them to test the local lifeforms in order to determine their thresholds. This as a result led to the deaths of numerous individuals in the settlement who died from heat, cold and various other incidents. The event attracted the attention of Lili Marquette and William Boone who had initially believed that it was a case of Companion Reaction Syndrome. They eventually discovered the probe which they believed was a hidden Taelon experiment and thus sought to secretly transfer it to the Liberation headquarters for study. Initially, they faced trouble from the probe as it unleashed a swarm of mechanical replicated butterflies capable of easily killing human beings due to sharp claws as well as razor sharp wings in their bodies. However, Boone using the power of his Skrill implant managed to destroy enough of them ontop of the probe to the point that their freezing internal liquids jammed the probes circuitry. This led to the deactivation of the replicated butterfly swarm and the probe entering into an inactive state allowing for the Liberation to arrive and take it for study. (Episode: Float Like a Butterfly)

Once within the Liberation headquarters, it was studied and the Human resistance members believed it was an advance probe of Taelon origin which was sent to study the inhabitants of Earth. Whilst the probe had been earlier disarmed, a power surge allowed it to reactivate whereupon it digitized Liberation scientist Rayna. Unaware of this, the Liberation scientists instead focused on where the probe was directing its transmissions which they concluded were being sent to a nebula on the other end of the galaxy from the Taelon homeworld. After creating two duplicates of Rayna, one of these replicants destroyed itself by tapping into the power supply of the Liberation base whilst the other ambushed Lili Marquette whilst she was examining the probe. Creating a shield around itself, the probe projected a signal into space to its creators. This alerted the Taelons who began to attempt to track down the probe before the machine coninued on its mission directive. Whilst the search for the probe continued, the Liberation had to contend with the probe disassembling into a dust configuration where it infiltrated the resistance's ventilation system. It was only William Boone's limited knowledge of the Taelon language allowed the Liberation to send a command to the probe to locate deuterium which the resistance had left outside their base. This allowed the Taelon security forces under Da'an to deactivate the probe and take it for study. (Episode: The Scarecrow Returns)

The fascimile of Rayna later abandoned the resistance headquarters during the events that led to the birth of the Human-Kimera hybrid called Liam Kincaid. The alien probe knocked out its guard escort and headed towards the Pentagon Alexandria base in order to tap into the communication system. Initially, it was barred from entering by a human guard to which the probe attempted to discern whether the planet wide jamming by the Taelon's was still in effect to which the security officer confirmed. Whilst attempting to move into the central computer, the human guard attempted to block the probes path which swiftly strangled him and dispatched him. After entering into the computers, it accessed and realigned the communication array whereupon it tapped directly into the system through a data probe beam emitted from its eyes. Its activities allowed it to beam a transmission into deep space and thus managed to penetrate the Taelon jamming allowing it to connect to its Jaridian masters. When a human military contingent arrived to discover what the commotion was, they discovered the probe had rearranged its body into its initial form. As the military officers arrived, the probe rearranged its body into a militant form which quickly dispatched the soldiers after which it began a planet wide database search for Taelon targets around the Earth.

Once its targets were located, the Replicant cloaked and began a search mode where it moved in secret to find its targets. Locating a funeral service for the Companion Protector William Boone and targeted a trio of Taelons present. Before it struck, a disguised Liam Kincaid quickly moved to save Da'an's life. However, the leader of the Taelon Synod was killed by the Replicant and despite being attacked by Ronald Sandoval, the Jaridian Replicant managed to escape. The death of a Taelon caused some shock to the Earth community and Zo'or refused to allow any Taelon on Earth until the Replicant was destroyed. Da'an later managed to convince Zo'or to allow him to meet with the humans at a press conference as part of a plan to draw out the Replicant and destroy it.

Later, when the US Companion returned to his embassy, the Replicant attacked the building with the intention of eliminating its target. Initially, it faced resistance from a degenerator field that was intended to shut down its systems through an EMP burst. However, the Replicant managed to survive and destroyed an interdimensional portal that was to be the escape route for Da'an and Liam Kincaid. Whilst the Jaridian war machine was combating the effects of the degenerator field, its targets escaped underground into the subterrainean tunnels. Following them, it cornered them and managed to easily survive the weapon fire from Liam Kincaid's pistol. After overpowering him, the Replicant turned its weapon limb on Liam and fired; however, its energy blast was absorbed by Kincaid's sharqarava organ and sent flying back at its source. The powerful energy blast destroyed the Replicant and shattered its body pieces across the floor thus ending the threat posed by it. (Episode: The First of its Kind)

Since the encounter of the probe, the Taelons were noted to had studied the replicants and attempted to decipher its command codes. (Episode: Message in a Bottle) Their understanding of the programming later allowed them in conjunction with human scientists to create the Bio-Surrogates. Whilst initially, these organic constructs were designed to provide a means through which disabled people could live their lives, the project was taken over by Zo'or who used the military programming of the Jaridian Replicants in the Bio-Surrogates to create supersoldiers. (Episode: One Man's Castle) Another Replicant was operating on Earth for sometime where it took on the Human disguise of a spin doctor known as Wagner. After the Companions began to face some negative public imagery, the Replicant used its disguise to board the mothership where it patched into the Taelon Mothership's computers where it overrided them. Sending the ship into interdimensional space, the aim of the Replicant was to take the Taelon ship and its ID technology to its creators. In order to secure its existence, it impersonated Liam Kincaid when taking over the navigational controls leading to suspicion being drawn on Kincaid. However, Kincaid was later freed and saw the duplicate version of himself talking to the journalist Abbey Franklin. During a scuffle, Abbey shot a blast at Wagner who reverted to its Replicant form. Undamaged, it managed to escape in order to ensure that the mothership was taken to Jaridian space. (Episode: Hijacked)

Sometime later, a Jaridian probe was dispatched to Earth where its vector meant that the Taelon Mothership was unable to intercept it. As it approached the eastern coast of North American, the Washington Embassy was ordered to fire its weapon to destroy it. Whilst the probe was hit, it managed to survive the attack and crashed on the planet. The resistance members managed to secure the probe in a dampening field but were themselves ambushed as well as captured by operatives from the secret government group known as Operation: Dark Knight. These soldiers took the probe to their secret stronghold in the mountains where they studied it in an attempt to get access to its advanced weaponry for use against the Taelons. They were later assisted in this act by Augur and the captured resistance members. It was eventually freed and broke through the facility and though it was initially believed to be hostile, it was revealed by the partially transformed Replicant that it had been sent to make contact with the natives on Earth in order to create a transmitter to allow the Human resistance contact with the Jaridians so that together they could destroy the Taelons. Whilst it was in the process of downloading the schematics to a transmitter, a Taelon strike force of Volunteers stormed the Mount Weather facility. In order to prevent its capture, Operation: Dark Knight detonated a low yield tactical nuclear device which destroyed the bunker along with the probe before it could complete its download. [Episode Message in a Bottle]