The world of The Flash got a whole universe bigger, as Barry Allen, Cisco Ramon and Harrison Wells took the jump from the world of The CW's Flash/Arrow universe to the alternate universe's 'Earth-2.' They found more than they bargained for, as familiar faces from the network's DC Comics continuity were re-imagined completely - putting some of the network's fan-favorite villains into the role of incompetent heroes, and turned lovable allies into cold-blooded killers.

What fans got were even more easter eggs, jokes, DC Comics references, and well-hidden homages than the characters could ever have hoped to spot. To guarantee that no fan of The FlashArrow, or even DC's Legends of Tomorrow misses out, we're here to break down each and every single bit of trivia and hidden easter eggs in The Flash's Multiverse-launching adventure, "Welcome to Earth-2."

Needless to say, there will be plenty of SPOILERS in our look at The Flash: Every Earth-2 Easter Egg & Hint Explained.

Dr. Henry Hewitt a.k.a. Tokamak

The Flash Earth-2 Tokamak

The first hint that the trip won't be as smooth or as tourist-friendly as Barry and Cisco had hoped comes when the group runs into one of S.T.A.R. Labs' assistants: Henry Hewitt (Demore Barnes). The pair recoil in terror since it isn't the first time they've crossed paths with Hewitt: he was once considered the prime candidate to replace Ronnie Raymond as Firestorm's 'other half.' But when a taste of that power led him into an angry, murderous rage, it was up to Barry and the newly-recruited Jefferson 'Jax' Jackson to bring Hewitt - a.k.a. Tokamak - down for good. Thankfully, a little appreciation seems to have kept this version under control.

Mayor Snart

The Flash Earth-2 Mayor Snart

As is usually the case, the universe-hoppers rely on the local news to get their bearings. Aside from the obligatory "Channel 52" label (a regular nod to DC Comics' weekly series, number of titles, and New 52 continuity), the report also claims that "Mayor Snart has extended curfew." It's surprising that such an uncommon name doesn't catch the attention of Barry or Cisco, since the obvious implication here is that Leonard Snart a.k.a. Captain Cold (Wentworth Miller) has wound up serving the public of Central City, not stealing from them. It's not hard to imagine, given his knack for leadership, but it's also not unheard of.

In the pages of DC Comics, Snart even wound up fighting for the people in the "Flashpoint" timeline (in which Barry Allen never became The Flash). Known as the local hero Citizen Cold, his methods were still a bit more brutal than politics would allow. We suppose it's possible that it could also be Snart's father in the mayor's office, but... he never seemed like the brains of the operation (whether that qualifies him for the job, we'll let the people decide).

Light Reading

The Flash Earth-2 Easter Eggs Two Cities

Once again, eagle-eyed viewers will spot that it's no random gun, but a "Model 00X52" Harrison Wells is carrying. But even sharp viewers are likely to overlook one of the best easter eggs that the minds behind the show clearly couldn't resist. A leather-bound book sits on Harrison's desk, and while it's difficult to make out, the book is about as fitting a story as could possibly be found in this episode: "A Tale of Two Cities" by Charles Dickens. Although in this case it's technically "A Tale of Two Universes," we would have to say the joke still works as intended.

A Just Society

The Flash Earth-2 Justice Society Mural

It didn't take long for fans of the show to notice there was more than stunning artistry at work in the massive sculpted mural in the lobby of the Central City Police Department. A closer look showed a stand-in for the Justice League (as if the massive "JUSTICE" wasn't enough of a hint), with seven Greek gods all reflecting a member of the famous DC Comics superteam. Apparently things went a bit differently on Earth-2, since the mural instead shows military officers and infantry, with the former saluting the latter. It's still a striking image, but the easter egg here is the mention of a "Just Society" - a nod to the Justice Society, the first name given to the team of DC Comics' Earth-2, Golden Age heroes.

A Cracked Shot

The Flash Earth-2 Deadshot

It turns out even stars of Arrow have a second life in Earth-2's Central City, as Floyd Lawon a.k.a. Deadshot (Michael Rowe) of the lethally unpredictable Task Force X (also known as the Suicide Squad) also makes an appearance. Unfortunately, the term 'Deadshot' still applies, only intended to tease the cop for his less-than-proficient (read: truly pitiful) marksmanship skills. Although that would explain why the Earth-1 version of the assassin is almost superhuman when it comes to firearms: possessing the skills of two universes' worth of his senses would give him more than and edge on the battlefield.

Singh Like a Bird

The Flash Earth-2 Captain Singh

Matching Deadshot's shift from one side of the law to the other is Captain David Singh (Patrick Sabongui). Where he's best known as a tough-but-fair police captain back on the show's primary Earth, his Earth-2 doppelganger apparently has as much of an eye for crime as he does for fashion (and painstaking grooming). Unfortunately there isn't enough time to find out what led him down this path as opposed to the other, but in keeping with his all-or-nothing mentality, the familiarity with the police working the station implies he's not a two-bit, but a career criminal. Which takes dedication, if nothing else (the same goes for the beard).

Killer Frost

The Flash Earth-2 Killer Frost

From the moment that the role of Dr. Caitlin Snow (Danielle Panabaker) was cast, fans have been expecting a turn to the dark side, since the name is bestowed upon a DC Comics supervillain, cursed with powers over ice as something of a 'heat vampire,' in her most sympathetic form. The version seen on Earth-2 is anything but sympathetic, having risen to the rank of a lieutenant of Zoom's, enforcing his will over the other criminals of Central City. She makes out better than her comic counterpart when it comes to her physical appearance, but even her bond with Ronnie Raymond is lifted from the comics (although it, too, is far more sinister here).

Now That's Square

The Flash Earth-2 Square Money

You have to hand it to the producers: they definitely know when to be subtle, and when to drive a joke home. If the golden hues, the bow ties, the polite demeanor of nearly everyone encountered, or the rayguns in S.T.A.R. Labs' lobby didn't tip you off, Killer Frost reveals that on Earth-2, even the money is square. It's a strange touch to make the world seem even more distant from our own, but the label on the bank note - Central City Royal Bank - should get fans of the British monarchy talking.

Deathstorm

The Flash Earth-2 Deathstorm

Just like Caitlin Snow, Ronnie Raymond (Robbie Amell) makes his return as the villainous 'Deathstorm.' While the character is pulled from the pages of DC Comics, it's truthfully only his name that's been adapted. It's for good reason, since the backstory of nearly all alternate/'bad' versions of Firestorm come with far too much backstory for a single episode. There's the version of Ronnie resurrected from the dead during DC's "Blackest Night" event, or our personal favorite, the soldier of The Injustice Society. Instead of merging his body with Ronnie Raymond, Martin Stein's research into creating life from the dead led him to merge with a corpse, becoming the being known as Deathstorm. Still, Ronnie being bad in black leather gets the job done.

Familiar Friends

The Flash Earth-2 Justice League Easter Egg

If you have the chance to make a Justice League reference in your DC Comics TV show, why wouldn't you? In fact, why wouldn't you in any TV show? When Barry and Iris arrive home, she lets him know that his still-very-much-alive mother has called. When Barry returns the call, the audience gets a clear view of the people on speed dial. Aside from Iris' father, Barry's parents, and 'Eddie' (apparently Barry's lack of a coma kept him out of the picture), the names Bruce, Hal and Diana are all visible. For the unfamiliar, that's a reference to Bruce Wayne (Batman), Hal Jordan (Green Lantern), and Diana Prince (Wonder Woman). Since it doesn't quite make sense for this Barry Allen to be friends with the League, we wouldn't bet on any cameos.

A Trip to Atlantis

The Flash Aquaman The CW Grant Gustin Season 1 Easter Egg Blu-ray DVD
Yes, we know that's Wally West, but the image is still appropriate!

It turns out that Earth-2's version of Barry Allen isn't taking his mother for granted as much as one would think, as the phone call reveals that he's sent his parents two tickets to Atlantis for their anniversary. The reference to the home of DC Comics hero Aquaman is easy to catch, but it raises all kinds of questions about the course of history in this parallel world. Was Atlantis never sunk by Vandal Savage (depending on who you ask)? Or has it been sunk, and reconstructed above the surface? Is there such a thing as underwater tourism on Earth-2? Sadly, we doubt we'll ever find an answer.

Velocity 6, 7, 8...

The Flash Velocity 9 Drug

From the moment that the existence of a superspeed drug called 'Velocity 6' was first established, comic book fans knew that it was a serious plot point in the making. Or, it would be, once a few more iterations and upgrades to the drug had been made. In the pages of "The Flash," the drug known as 'Velocity 9' was a major headache for Wally West, getting innocent people hopelessly addicted to the euphoric rush of speed it gave them. Engineered and distributed by Vandal Savage, the drug posed a problem for The Flash not only because of his enemies using it to get an edge, but the innocent civilians it was sending to their death around him. We can only hope that once this version is reached on the TV show, Jay Garrick will have learned that it's not worth the risk.

That's Using Your Hat

The Flash Jay Garrick Hat Punch Easter Egg

Once Jay decides he can tackle the drug problem with Caitlin at his side (or in his ear), he shows that his hat is more than just a decoration. While the villainous Geomancer tries to crack the ground beneath his feet, he fires a series of punches into the convex side of his helmet, sending powerful shockwaves into his opponent. Viewers might have been stunned to see his formerly-dated headgear come in so handy, but comic readers are already familiar with the trick. Although a bit older than his fellow speedsters, Jay Garrick let the same punch fly to just as effective a result.

Reverb

The Flash Earth-2 Cisco Reverb

It came as an extra cruel twist of fate when Cisco Ramon got his wish of meeting his doppelganger, only to realize that his Earth-2 self was working for Zoom. Sporting the goggles from the comics (but an evil mission not found in his source material), the doppelganger revealed that while Earth-1 Cisco had chosen the name 'Vibe' for his powers, his Earth-2 version went by the name 'Reverb.' In the comics, Vibe's death led to one of his younger brothers, Armando Ramon, to pick up his role as a metahuman crimefighter, using his own shockwave abilities as 'Reverb' before changing his name to 'Hardline.' We would agree with Cisco that 'Reverb' isn't too bad a name, all thing considered.

NEXT: How The Flash Just Confirmed DC’s Shared TV Multiverse

Those are all the easter eggs, secrets and tiny touches we spotted in The Flash's visit to Earth-2, but we're almost certain there are some we missed. Let us know which easter eggs you caught in the comments, and we'll expand the list as more secrets are discovered.

The Flash airs Tuesdays @8pm on The CW.