"You might as well talk to him, Superman." Batman's sharp gaze cut across the long table. The superhuman had been on edge for weeks now and it was starting to interfere with his focus in combat. The Flash watched the powerhouses carefully, his polite discretion lost after Superman faltered during the Justice League's last encounter with Clock King.
"I think it's about time you came clean, Superman. What's going on?" Martian Manhunter floated down from the floor above, preparing to defuse a conflict should one arise. The Kryptonian stood, refusing to respond to his team mate's question.
"Whatever's going on, it's becoming dangerous." Barry watched his friend cringe under his scrutiny.
"It's been dangerous all along, Flash."
"What has?" The speedster spoke quietly, as though Superman would run away at any moment.
"Cadmus. Experiment 13. It just doesn't add up…" Manhunter and Batman looked at Flash for a moment, waiting for him to start connecting the dots. "Cadmus shouldn't have been able to create a clone of me without a livingsample. "
"They would have needed to see your DNA functioning in order to create a copy. All of the research we've found from Cadmus and Experiment 13 have been of human/Kryptonian hybrids. They could have used a living human sample and infused it with Kryptonian DNA." Batman looked at Superman and Martian Manhunter, waiting for their conclusions.
"I'm not sure I understand what you're saying… Experiment 13… that was Superboy. If they didn't have your living tissue, then wouldn't that make him…?" The Flash looked between Superman and Batman.
"Then he wouldn't really be a clone after all." Superman could feel his mind reeling. It was different to think about the possibility, but when all of the data came together like this, and when it was all out in the open, it quickly became overwhelming.
"How long have you guys known about this?" Flash remembered Superboy's distress when they met at the tower. He was looking for answers from Superman at least a week ago. Superman and Batman exchanged a glance.
"Well… I thought that I might have missed something about the cloning process, or that there might just be differences but…"
"Superboy is left-handed, Flash. Dominant handedness is believed to be genetic, and even if it wasn't, Superboy's implanted memories would have caused him to favor his right hand like Superman."
"How long have you known?" The Flash looked accusingly at Batman.
"Since I saw him that night." Batman returned the speedster's stare, refusing to back down. The Flash started to relax and look at the situation more rationally.
"So who would they have used?" Flash looked from Batman to Superman and Batman followed his gaze to Superman. Superman thought about the only left-handed person he knew who Cadmus would choose for the genetic splicing. He remembered the cold glare the man had given him the last time they'd met, and the Kryptonite injection which had followed it. Odds were pretty good that he and Batman were thinking the exact same thing, and Batman was sure to have a mountain of proof to back it up. Somewhere delving deep in Cadmus's data files Batman must have found the name which could make even Superman shiver; Luthor.