Deral was the captain of Servalan's command ship, although his authority appeared to be mostly nominal, with Servalan giving the orders herself. He assisted her in infecting Pilot Four Zero with an alien pathogen but expressed concern over breaking Auron's neutrality. Servalan told him it was necessary to rebuild the Federation but admitted she also wanted to make use of their cloning facility. When Deral again expressed disapproval, she told him he was lucky she needed officers who were loyal and wouldn't interfere. She also revealed her main objective was to capture the Liberator.
After arriving on Auron, Deral was again mostly cut out of the conversation as Servalan ordered Ginka to give the cure to Franton. Deral attempted to tackle Ginka over insubordination but Ginka doubted Servalan would allow Deral to court-martial him and made it clear he believed Deral had only been made captain ahead of him because he had connections. Deral accompanied Servalan to the replication plant where she had a clone batch injected with her DNA.
When Avon, Tarrant and Cally were taken prisoner, Servalan had Deral teleport up to the Liberator as her deputy, supposedly to negotiate in person but really to take control. However, although he held Vila at gunpoint, he was quickly surprised and disarmed by Dayna and Patar. They quizzed him about the cure Servalan had; Deral said he had no chance with Servalan if he helped them and Vila told him he was dead to her either way.
After Avon and the others escaped, Deral correctly predicted they would go to the replication plant, since Servalan wouldn't risk killing her children by firing on it. This allowed Dayna to teleport down and retrieve most of the party. Despite this and despite his protests, Avon and Tarrant promptly teleported him back to Servalan's ship, telling him to tell her that they'd escaped with the Auron brood units. Deral had little chance to do so: Almost as soon as he appeared, Servalan killed him with the push of a button. (C: Children of Auron)