Brainiac has been traveling throughout the Universe and gathering information about several planets since "The Last Son of Krypton."
This episode features for the first time the place what will later be known as Superman's 'Fortress of Solitude.' It is located in the Arctic.
The large back truck appearing in the beginning of this episode is basically and large model of the Batmobile from Batman: TAS.
When Brainiac first establishes contact with Luthor and then his holographic image disappears, there are two frame shots of Krypton blowing up in-between the shots.
Councilman: So, Mr. Luthor, how long did you intend to keep your rendezvous a secret? In case you haven't heard there's a thing known as National Security.
Lex Luthor: There's also a thing known as free enterprise. It was LexCorp that scanned the heavens, it was LexCorp that made contact and it will be LexCorp that reaps the benefits.
I apologize for any discomfort, but it was important that I accurately gauged your powers.
Why? Morbid curiosity?
Curiosity, yes. Morbid, hardly. You see we have more in common than you could possibly know, Kal-El.
How do you know my name? Have you been to Krypton?
Superman: It was several hours after I touched the orb that I saw the images. It's too soon to trust him completely.
Lex Luthor: (laughs) I never trust anyone completely. Since Brainiac arrived I've had him targeted from land base platforms with a payload of six and a half megatons. Enough firepower to incinerate Metropolis county.
Superman: "Keep your friends close, but your enemies closer."
Lex Luthor: Precisely. Although in your case, I'll make an exception.
You destroyed those planets, didn't you? And every living soul on them!
Only their knowledge was important. It was what I was programmed to collect and protect.
But why kill?
The few beings who have the knowledge, the more precious it becomes.
your father's son, Kal-El. Headstrong, foolish, easily defeated and ultimately forgotten.
Programmer: It'll take years to rebuilt these systems.
Lex Luthor: You have two weeks.