The Profundity, an MC75 Star Cruiser under the command of Admiral Raddus, served the Alliance Fleet. A significant moment for it was its presence during the Battle of Scarif. Soon after the Death Star plans were transmitted to Raddus, the vessel was disabled by the Star Destroyer Devastator, leading to a boarding action by Darth Vader who sought to retrieve the stolen data tapes.
While the Dark Lord advanced through the starship's corridors, a small team of Rebel troopers managed to escape aboard the Tantive IV, which was docked to the Profundity, passing the plans to Princess Leia Organa.
Initially, the Profundity functioned as the civic governance tower for the city of Nystullum. As was common with Mon Calamari structures, the tower was transformed into a ship and became part of the exodus fleet that left the Mon Calamari homeworld under the leadership of Raddus, who had been the city's mayor. The ship's crew largely consisted of former defense personnel from Nystullum. Upon the Mon Calamari joining the Alliance, the Profundity was among the first vessels converted into a warship. When Rogue One's mission to Scarif became known, Admiral Raddus assembled as many ships as he could muster to provide support. Arriving at Scarif with the Alliance Fleet, the Profundity participated in the battle, serving as the command vessel for the Alliance forces.
As the battle drew to a close, the Profundity successfully intercepted the Death Star plans transmitted to it by Jyn Erso of Rogue One. However, before the cruiser could escape with the acquired data, the Devastator rendered it immobile, and Darth Vader boarded in an attempt to recover the stolen plans.
Several Rebel troopers from the Tantive IV downloaded the plans onto a data tape and attempted to flee to their ship located in the Profundity's docking bay. Just as the Rebels reached the door, a mechanical failure caused by battle damage caused it to jam. Moments after the door became stuck, Vader arrived in the hallway. The rebels resisted Vader for as long as possible until one trooper managed to pass the plans through the crack in the door to their fellow crew on the ship. The corvette then rapidly departed the vessel, leaving Vader stranded in the bay. The Profundity was ultimately destroyed by the end of the conflict.
The initial appearance of the Profundity was in Rogue One: A Star Wars Story, a film directed by Gareth Edwards. Its name was first established in Star Wars: Rogue One: The Ultimate Visual Guide by Pablo Hidalgo. Early concept art referred to it as the "Rebel trawler." An adventure seed in Starships and Speeders, a 2020 sourcebook for the Star Wars Roleplaying series by Fantasy Flight Games, indicated that the Profundity was discovered intact, and the Empire intended to use it as a target for weapon testing.