Benthic, known also as "Two Tubes" or simply "Tubes," was a male Tognath mercenary pilot who fought alongside Edrio, his brother and eggmate. The nickname they shared came from the breathing equipment that enabled them, given their Tognath biology, to function in oxygen-rich atmospheres. Benthic's homeworld of Yar Togna was seized and occupied by the forces of the Galactic Empire, which forced him to become a refugee by fleeing. Eager to retaliate against the Empire, Benthic became an ally of Enfys Nest and her Cloud-Riders; later, sometime before the Battle of Yavin, Edrio and Benthic joined forces with Saw Gerrera.
Benthic's birth occurred in 32 BBY on the planet Yar Togna. At some point during the Age of the Empire, the Galactic Empire conquered his world, leading Benthic and his eggmate brother, Edrio, to escape and become refugees. While many members of his species were taken advantage of by criminal organizations such as Crimson Dawn after they were forced to leave their homeworld, Benthic chose to join Enfys Nest's Cloud-Riders, a pirate group that sought vengeance on the Empire and the crime lords who oppressed his people. In 10 BBY, Benthic went with Nest and the other Riders to a rendezvous on Savareen with Han Solo and his crew, where they successfully persuaded them to betray Dryden Vos of Crimson Dawn, which resulted in the Riders acquiring the coaxium.
Later, desiring to fight back against the Empire, Benthic and Edrio enlisted with the Partisans, a rebel group led by Saw Gerrera, and Benthic eventually rose to become Gerrera's second-in-command.
In 5 BBY, Benthic, along with the Partisans, was based at a base located on the planet Segra Milo. While the rebel Luthen Rael was inside speaking with Gerrera, offering the Partisans a mission to assist rebel Anto Kreegyr, the Tognath stood guard outside. Saw declined to risk his forces on the attack, dismissing Kreegyr as a Separatist, but later changed his mind and decided to accept the mission.
When Rael returned, Benthic and some fighters intercepted him as he approached the base. The Tognath ordered Luthen to halt and demanded that he be searched. Rael questioned the order, but Benthic replied that Saw was in such a mood. After the fighter searched Luthen and removed a staff, Rael requested that they either put it down or return it to him. Annoyed, Benthic escorted Luthen further into the base, where Saw was waiting.
Upon their arrival, Gerrera asked Rael to inform Kreegyr that the Partisans would assist him in attacking the Spellhaus Imperial power station, but the rebel advised Saw against it, warning that the Imperial Security Bureau had set a trap for Kreegyr and his men, and thus assisting would endanger their rebellion against the Empire. During the argument that followed, Saw questioned Luthen about the people who provided him with information, asking if he had an agent within the Partisans. He was surprised when Rael claimed that Benthic was his informant, but when the Tognath moved forward to deny it, Luthen seized Benthic's DT-15 blaster pistol and aimed it at Saw, which caused Benthic to retreat. After a brief standoff, Rael convinced Saw to let Anto be sacrificed for their mutual benefit and departed from the base.
In 1 BBY, the Partisans were participating in an insurgency against Imperial forces on the desert moon of Jedha. Later, the Imperial pilot Bodhi Rook defected from the Empire and sought out Gerrera with a message from Galen Erso. Benthic and a group of Partisan soldiers met with Moroff, the Gigoran mercenary, who had brought Rook to them. After a brief interrogation, Benthic ordered his men to blindfold Rook and take him to Gerrera for further questioning. After they brought Rook to Gerrera, Benthic handed Gerrera Rook's identicard and datastick containing Erso's message, claiming he had found them in Rook's boots, which Rook denied.
Soon after, Benthic led a group of soldiers in an ambush targeting an Imperial kyber transport. During the intense battle in Jedha City, Cassian Andor, who had traveled to Jedha with Jyn Erso in search of Gerrera, killed one of the Partisans in self-defense to protect Erso, an act witnessed by Benthic. Following the defeat of the Imperial transport, Benthic mistook the pair for enemies and ordered his troops to restrain them, along with Baze Malbus and Chirrut Îmwe. They were taken to the Catacombs of Cadera, where Benthic delivered Jyn to Gerrera, while the others were imprisoned in cells within the catacombs. During this time, Director Orson Krennic of the Empire ordered the Death Star to destroy Jedha City. The resulting shock wave caused the Partisans' nearby hideout to collapse. Benthic quickly evacuated his fellow Partisans into escape shuttles and then escaped the base himself. His brother Edrio died during the destruction.
After the Battle of Yavin, Benthic led the remaining Partisans in their ongoing fight against the Empire on Jedha. Later, Benthic was approached by representatives of the Rebel Alliance, including Princess Leia Organa, Luke Skywalker, and Captain Han Solo. Initially, Benthic considered killing them. However, Organa offered the Alliance's continued support to the Partisans on Jedha, informing him that the Empire intended to continue extracting kyber crystals from Jedha. Despite his reservations, Benthic accepted Organa's offer and discussed the terms of their alliance.
At Ai-jed, Benthic, accompanied by Skywalker, witnessed the Empire's latest defilement on Jedha. Benthic assured Skywalker and Solo that they would destroy it.
Some time later, Organa enlisted Benthic and his Partisans for a mission to Shu-Torun. The objective of the mission, led by Organa, was to inflict a devastating blow to Shu-Torun's economy. Benthic agreed to participate because it offered him an opportunity to destroy an Imperial world, disregarding Organa's other goals. Upon arriving on the planet, Benthic and his crew quickly devised a plan to obliterate the entire world—an even greater destruction than what happened to Jedha. Benthic discovered that destroying the Spike would result in the complete annihilation of the planet and everyone on it. With the coerced assistance of R2-D2 and a subdued Skywalker, the Spike was prepared for demolition.
However, Organa intervened and convinced Benthic not to destroy the Spike, arguing that it was not the "dream" of the Partisans, an ideal that originated with Saw Gerrera. Benthic relented, and they escaped Shu-Torun aboard the Millennium Falcon. Benthic requested that he and his Partisans be dropped off at Salobea, describing it as "something else for the Partisans." After arriving there, Solo reminded Benthic of their first encounter when Benthic was a member of the Cloud Riders, and advised the leader of the Partisans that he did not have to be bound to any particular path, especially with the right motivation. Benthic took these words to heart, suggesting that he would change his ways.
Benthic made his debut in the 2016 Star Wars Anthology film Rogue One: A Star Wars Story, portrayed by Aidan Cook. His name and species were revealed at San Diego Comic-Con in 2016.