Steven Mandragora was a powerful crime boss who had once murdered the parents of Helena Bertinelli.
Steven Mandragora was once the most frightening chief enforcer for crime boss Franco Bertinelli. One day, Mandagora grew tired of taking orders, so he turned on his boss and murdered him, together with his wife. Unknown to him, Franco's young daughter, Helena, watched the murder from the closet where her father had hidden her, forever scarring her. Mandragora then became a criminal kingpin himself. At some point, he married and had a son. Helena grew up to become the vengeful vigilante Huntress and joined the Justice League.
Several years later, Mandragora was in federal protective custody, but whether because he had been arrested or had turned himself in was unclear. In return for immunity from prosecution, he agreed to testify to a grand jury investigating organised crime. He was taken to a safe house since the League suspected, rightfully, that the Huntress was out to kill him.
In the safe house, Mandragora was questioned by FBI agent King Faraday about his business associates and rivals, but was very vague about details. He also disgusted the others present with his horrible table manners and antagonised Green Arrow and Black Canary, who were part of the security detail, with lewd humour and insulting remarks, which resulted in them attacking him and being dismissed from the house.
Secretly, he was merely stalling for time while his underlings were rescuing his son, Edgar, from a rival gang who had kidnapped him while they were abroad. Once Edgar was safely on his way back to the United States, Mandragora escaped custody and planned to disappear with his son under new identities and a fortune in a hidden bank account.
With the aid of the Question, Huntress caught up with Mandragora just as he was reunited with Edgar. Huntress saw that the man who killed her parents was now a loving father. She had planned to execute him, but the appearance of his son changed her mind: it revealed a more human side to him and she was not willing to put another small child through the horror she had experienced.
Instead, she thwarted his plans to disappear and he was returned to federal custody, now left with no choice but to cooperate for both his and his son's sakes.
Powers and abilities
Mandragora proved himself to be a powerful opponent with some degree of invulnerability, especially against many forms of blunt-force trauma. He was able to resist Black Canary's sonic 'Canary Cry' as well as explosive/stun arrows from Green Arrow and a crate being dumped on him from a big height. However, it does seem he could potentially be killed by more lethal means, as he surrendered when the Huntress threatened him with her crossbow arrows.
He also possessed a certain degree of super-strength, revealing that despite his fatty appearance, he is mostly muscle. He has shown that it's likely for him to kill people in one slam of both his arms.
In the comics, Mandragora was the Mafia boss who ordered the murders of the Bertinelli family. His animated version is more closely based on the comics character Tobias Whale.
Though he is an ordinary human in the comics, here Mandragora's strength and endurance hints that he has metahuman powers, a supposition bolstered by the fact that his son, Edgar, later appears as a powerful psychic in Batman Beyond and The Zeta Project.
The fact that they are both white-haired, pale-skinned and have pink eyes indicates that the Mandragoras are albinos.
The end credits of "Double Date" lists his name as "Mondragora", though it is pronounced "Mandragora" by every character in the episode and is spelled as such in his DC Comics appearances. "Mandragora" is also the medieval name for the poisonous Mandrake plant.