Lobo Easter Egg in "Crisis on Earth-X Part 1"

Dozens of DC superheroes and supervillains are coming together this week for 'Crisis on Earth-X,' [...]

Dozens of DC superheroes and supervillains are coming together this week for "Crisis on Earth-X," the third annual CW/DC Universe crossover event and the largest yet. Someone not in attendance? Lobo, the spacefaring bounty hunter who was introduced as a foil for the Omega Men but went on to become one of the most popular characters of the 1990s.

The character has not yet appeared in live action (one truly amazing fan film notwithstanding), but tonight, while Supergirl fought a Dominator -- "That's so last year" -- members of the DEO staff were listing possible alien threats and buzzed right by "Czarnians."

Lobo is the last Czarnian -- the same way Superman is the last* Kryptonian, and Martian Manhunter is the last* Martian. In Lobo's case, though, he was not sent to Earth fleeing a catastrophe; he was the catastrophe, murdering most of his world's inhabitants.

This is not the first time Supergirl has got fans talking about Lobo; during a 2016 episode, the DEO whispered in hushed tones about "him" -- an unnamed but obviously dangerous interstellar bounty hunter presumed by many to be Lobo.

Lobo has had a variety of roles in the DC Universe, but mostly falls into the category of "antihero." He has been a villain for Superman and the Omega Men, among others, but has also been part of the L.E.G.I.O.N. and currently serves on Batman's Justice League of America. For more about the whys and hows of that relationship, check out Wednesday's issue, which is heavily Lobo-centric.

His primary role, though, has been not as a villain or as a hero, but of the "hero of his own story," starring in a long-running series that saw him massacre his way across the cosmos, usually for some vaguely-defined good but sometimes just for comedy.

"Crisis on Earth-X" began tonight at 8 p.m. ET/PT and will run for two hours per night, today and tomorrow. Unlike last year's crossover, which skewed heavily episodic and could be joined at more or less any point, "Crisis on Earth-X" is shot like a movie, and if you missed tonight's episode of Supergirl and Arrow, your best bet may be to wait until the episodes are on The CW app tonight or tomorrow morning so that you can get caught up ahead of The Flash, which picks up the second half of the story at 8 p.m. tomorrow.

*"Last" is used very liberally here, since Supergirl and Reign (at least) currently exist, and J'Onn has not only his father but apparently dozens (or more...?) of White Martians.