The relationship between Batman and Nightwing, that is, Bruce and Dick Grayson, is actually akin to that of an adoptive father and adopted son.
Dick Grayson was originally an eight-year-old circus acrobat, the youngest member of the trapeze family known as the "Flying Graysons." They were well-known in Gotham City's circus scene and were the most popular trapeze act in the area.
Because the local gang was refused protection money by the circus owner, they retaliated by soaking the trapeze rope in a potent acid. During the performance, the rope snapped before Dick could jump, and his unsuspecting parents fell to their deaths before his eyes.
Orphaned, Dick was adopted by Bruce Wayne, a philanthropist and well-known business magnate who had been present at the performance.
Bruce, seeing Dick's tragedy, was reminded of his own past and adopted him. Dick soon discovered that Bruce was in fact Batman, the mysterious protector of Gotham City.
Bruce then began teaching Dick combat and detective skills, putting him through rigorous physical training and grooming him to become Robin.
Robin became Batman's first sidekick, the original Robin.
Over time, Robin matured. Dick, going through a rebellious phase, wanted to prove he could surpass Batman and began seeking more independence.
At that point, Batman didn't know how to be a qualified adoptive father, and the two clashed. Eventually, Batman "fired" Dick with good intentions, refusing to let him continue as Robin. In a fit of anger, Dick ran away and went to Blüdhaven, a city near Gotham, to fight for justice on his own.
Even so, every time he appeared as Robin to save others, people would always ask, "Where's Batman?" Tired of being in Batman's shadow, he decided to abandon the Robin identity and became "Nightwing."
This was the origin of Nightwing.
Additionally, the Grayson family—going back to Dick's grandfather—had a dark history of being turned into murder puppets called "Talons" by the Court of Owls.
"Bruce, I think you need me right now."
Nightwing spread his arms next to Bardi, a smile tugging at the corners of his lips. Being able to help his adoptive father again made him feel warm inside.
Nightwing's plan was simple.
Bruce would admit publicly that he was Batman and then kill the Joker in front of all of Gotham.
Then, all Nightwing had to do was put on the Batsuit, disguise himself as Batman, and appear alongside Bruce. That would be enough to sever the association between Bruce and Batman. Gotham would think it was all a staged trick pulled by a bored billionaire.
It was a simple way to cover up the fact that Batman had killed the Joker.
Otherwise, if it became known that Batman was Bruce Wayne, Bruce would face prosecution from the city, the state, the police department, the courts, and even Wayne Enterprises would suffer massive fallout.
Bardi bent over a microscope, examining Barbara's blood. The cells had already been corroded by Joker toxin. Drawing from the vast medical knowledge in his mind, he began decoding the virus within minutes.
He had no need to clear his identity as Batman. Everything Bardi did—every action, every word—was already accounted for. Killing the Joker didn't hinder his plans at all.
"So you want to go to jail? Bruce, Batman's identity alone is enough to land you in prison for four hundred years! Do you even know how many crimes Batman's committed? Murder, assault, abuse, theft, breaking and entering, robbery… fine, everything except rape!"
Nightwing couldn't believe it. He followed behind Bardi, still trying to talk him out of it.
He just couldn't accept that Batman would willingly go to prison.
"Bruce, if you have another plan, tell me. I can help you. I'm still your Robin."
Bardi was silent. It was true that Batman had committed many crimes, but most had already been erased or covered up by him.
His face darkened as he took a step forward, pulled out a test tube, found penicillin, and large doses of albumin, α1-, α2-, β-, and γ-globulin, triglycerides, total cholesterol, and alanine aminotransferase-based compounds. He adjusted the cryo-chamber to minus 58 degrees and began synthesizing an antidote for the Joker toxin using a compound with antidepressant and cleansing properties.
As the serum began to take form, Bardi remained expressionless, treating Nightwing with the same cold, methodical seriousness Batman always had.
In the sterile white lab, Bardi worked in silence, adjusting the serum with a focused expression, while Nightwing leaned anxiously against the wall, tapping the floor with his foot. No matter what, he couldn't hide the concern on his face.
Bardi let out a breath of relief. Barbara had been saved.
Killing the Joker had already crossed a major line. If Barbara had died, Batman's future actions would have been hampered by the psychological backlash.
He couldn't let Batman's behavior deviate too far from what the world knew of the original Batman. That would raise suspicion. Killing the Joker was already pushing the limit.
If it hadn't been for an immediate threat and a moment of extreme danger, there would've been no excuse to kill the Joker.
After preparing the serum, Bardi handed it to Alfred and instructed him to inject Barbara with it.
Then, without a word, his hand moved faster than lightning. He grabbed Nightwing's chin, pressed down with his thumb, and with a painful "ah" from Nightwing, forced out one of his teeth. Blood poured from his gums, staining his lips.
"Are you crazy, Bruce?!"
Nightwing clutched his jaw, staring in disbelief at Bruce. His expression was straight out of a melodrama: You hit me? You actually hit me? You knocked out one of my teeth?
Bardi picked up the tooth Nightwing had lost. It looked like a normal tooth at first, but it was inlaid with amber gold and a tiny owl.
"What… what is this? My tooth, why does it look ??"
Holding the spot where the tooth had come out, Nightwing winced from the dull ache. Bruce had used too much force, and blood continued to trickle out.
Seeing how strange the tooth looked, with an owl symbol embedded inside, he momentarily forgot the pain and stared at the object in Bardi's hand.
"Take it in for testing. Then come with me tomorrow night."
Without offering any explanation, Bardi tossed the tooth back to Nightwing and told him to get it tested himself.
Everything would be revealed tomorrow.
After Nightwing left the lab, Bardi began preparing again—mixing euphoric incense, neurotoxins, and mind-controlling drugs. He needed to gain control of the entire Court of Owls.
That would mean taking control of 70% of Gotham's upper-class society, giving him complete influence over the city's direction.