Cutup, identified as CT-4040, was a clone trooper who fought for the Grand Army of the Republic throughout the duration of the Clone Wars. As a member of Domino Squad, Cutup underwent training on the planet of Kamino prior to being stationed at a listening post situated on the Rishi Moon. In the year 22 BBY, Rishi Station came under attack by Separatist commando droids, which forced the troopers to evacuate. During their attempt to escape, Cutup was ambushed and consumed by a massive Rishi eel.
CT-4040 was born on the planet Kamino as a clone derived from the bounty hunter Jango Fett.
Being a member of Domino Squad, CT-4040, along with his fellow clone troopers CT-00-2010, CT-5555, CT-782, and CT-1409, were facing the prospect of being assigned to sanitation duties due to their consistently poor performance during training exercises. Despite each member of the squad possessing individual shortcomings, one of their drill instructors, the Siniteen named Bric, placed the blame for the squad's failures squarely on CT-4040. One evening, preceding their final attempt at the Citadel Challenge training course, CT-4040 encountered Bric within the hangar, where Bric reprimanded him, stating that he treated everything as a joke and that he was incapable of taking his own training with any degree of seriousness. However, CT-4040 simply laughed and chose to embrace the nickname "Cutup" after Bric used it to address him. Despite seemingly being unaffected by the conversation, Cutup and his brothers, who each experienced a renewed sense of purpose in their own ways, united and resolved to successfully complete the challenge. They made significant progress in the initial phases, but eventually, Cutup and his squad discovered that they had been sabotaged and were missing their ascension cables, which were essential for scaling the citadel's walls. Although Bric was responsible for the sabotage, the squad utilized their resourcefulness and devised a method to complete the challenge regardless. Ultimately, Cutup and his squad received their commissions and were deployed to participate in the ongoing Clone Wars.
Due to the escalating demands of the war, more and more troops, including the inexperienced Cutup, were rushed into service before their intensive training programs could be fully completed. Cutup and his Domino Squad comrades were stationed at a listening post known as Rishi Station, which was located on the Rishi Moon. In the year 22 BBY, as part of their strategy to launch an assault on the clone troopers' homeworld of Kamino, the Confederacy of Independent Systems initiated a surprise assault on Rishi Station. As BX-series droid commandos began to overwhelm the listening post, Cutup, along with CT-5555, nicknamed "Fives," CT-1409, known as "Echo," and CT-782, "Hevy," were compelled to escape through a ventilation shaft. Upon exiting the outpost, they found themselves on the surface beneath the station. However, a Rishi eel suddenly appeared and attacked Cutup, resulting in his death. The remaining clone troopers eventually succeeded in alerting the Galactic Republic about the Separatist assault, thereby preventing a potential invasion of Kamino.
The character "Cutup" made his debut appearance in "Rookies," which was the fifth episode of the first season of The Clone Wars TV series, and was originally broadcast on October 24, 2008. He also appeared in the third season's initial episode, "Clone Cadets," which, chronologically, takes place before the events of "Rookies." In these episodes, his voice was provided by Dee Bradley Baker, who is responsible for voicing all of the clone troopers throughout the entirety of the series.