Like his fellow deckmen, Deckman 5 was a cylindrical cyborg with a pair of hands. His distinguishing features were a short, pointed nose with a rounded tip, full cheeks, and buck teeth. Initially he had the number 12 on his chest despite being called number 5 by the rail mercenary chief, but this was later corrected.
In ES 590, Deckman 5 was assigned to operate Factory Train 12 from the Scrapyard to Factory Farm 22. He was first shown during the recruitment for rail mercenaries to guard the train. Among the passengers on the train were Alita as well as Figure Four and Yolg, who were serving as rail mercenaries. The train's systems failed to pick up Knucklehead's ambush force, but they were detected by Support System Gabriel. During the attack, Gabriel also detected that explosives had been planted on the track, prompting Alita to command Deckman 5 to stop the train. However the track was blown before the train could stop, derailing it. Deckman 5 survived the derailment, but was mortally damaged. He was able to warn Figure that a meltdown of the train's nuclear reactor was imminent, as well as inform him that the rent-a-gun computer had been damaged. He then started to sing the opening lyrics of Daisy Bell before he was killed in the subsequent explosion.