When last we saw The Flash, a mammoth black hole was hovering over Central City as the Scarlet Speedster raced toward it to save the day. It seemed like typical superhero fare at first, but as Barry Allen approached the hole, the screen just went black Sopranos style, and viewers were left to wonder about the fate of the show’s main characters.

(Spoiler alert: They're doing just fine)

However, what about the aftermath of the black hole? What tears in the very fabric of existence did it cause? What will this new status quo look like moving forward?

We know that the second season of the show will include more time travel, alternate realities, multiple Earths and even different versions of the Flash himself. How is all this head-spinning multiverse muckity muck actually going to work? Why is there suddenly another Flash running around with a saucepan on his head from someplace called Earth-Two?

Well, as with most things in life, the answers lie somewhere in the pages of a comic book.

Crisis On Multiple Earths

Anyone who has ever opened a DC comic surely understands, or at least attempts to understand, the theory of the multiverse. In the world of DC, there is a near-limitless amount of Earths existing in countless parallel universes, all inhabiting the same space but vibrating at different frequencies.

Confusing as it may be, it’s actually an endearing trademark of the publisher, and the first place this idea ever popped up was in none other than an issue of The Flash … Flash #123, to be more specific.

This was the legendary “Flash of Two Worlds” story, where Barry Allen — the rebooted Flash from 1956 — met Jay Garrick, the original Flash who was originally created in the ‘40s but slowly sunk into obscurity in the years after WWII before fizzling out completely in the early ‘50s.

This is where it gets complicated (actually, everywhere is where this gets complicated). Barry Allen is from an Earth designated as Earth-One, whereas Jay Garrick inhabits Earth-Two.

Earth-One is home to the Kal-El version of Superman, the miserable take on Batman we all love, the sprawling Green Lantern Corps, the Justice League of America and pretty much every other DC staple you know from pop culture.

Earth-Two, however, features the Garrick Flash, the Alan Scott Green Lantern and the rest of the Justice Society of America — all of whom operated during WWII and looked about as threatening as your local PTA:

On Earth-One, the characters from Earth-Two actually do exist, though, as literal comic book characters. So, Barry Allen — in trademark comic book logic — actually used to read Flash comic books growing up, which starred Jay Garrick. This is where he got the idea for his own Flash persona when he got his powers.

That all changed during “The Flash of Two Worlds,” when Allen was transported to Earth-Two and realized that these characters were indeed real people inhabiting another plane of existence. Over the years, Garrick and Allen — as well as the other heroes of Earth-One and Earth-Two — met countless times, with every reality converging together into the DC multiverse.

While Earth-One and Earth-Two are the main realities at DC, there have been some 50+ other Earths introduced over the years, all with different themes and gimmicks, such as an Earth with an all-black Justice League, a world with a pirate Justice League and a world where our favorite heroes are all filthy communists.

So, What Does This Have To Do With The Show?

You may remember during The Flash’s season finale, when the wormhole was first opened up in STAR Labs, a strange helmet made its way into the show.

Look familiar?

That’s Jay Garrick’s helmet from the comics. At first, people thought this might have just been a throwaway Easter egg, but it was later revealed that Teddy Sears will play the original Flash during the second season of the show. No longer a wink to the fans, Garrick will have a major impact on the series moving forward.

In the comics, Barry usually travels between universes through the use of his — sigh — cosmic treadmill. Literally, it’s a treadmill that uses DC’s tenuous grasp on physics to allow the Scarlet Speedster to travel to other Earths and through time on a whim.

Thankfully, it seems like the show will go for the much more palatable explanation of the wormhole to explain why multiple Earths will be on a collision course this year.

This opens up countless possibilities for stories as alternate versions of heroes and villains can pour through from Earth-Two at any time to help Flash battle the bad guys, or to simply wreak havoc on the multiverse.

Though it’s easy to assume that Jay and Barry will eventually work together, we don’t even know if these two speedsters will be able to co-exist. Maybe Garrick will simply travel to Earth-One to trade blows with this “other” Flash.

Alternate Realities

Earth-Two is only the tip of this convoluted iceberg that is The Flash, because the first season also dealt with plenty of alternate realities to choose from. In fact, the entire first year of the show was an alternate reality — thanks to the Eobard Thawne/Harrison Wells storyline — that was never actually supposed to exist in the first place, as producer Andrew Kreisberg explained to Entertainment Weekly:

"We established in the finale that the entire series of The Flash is, in itself, an alternate timeline that’s been skewed from the real one. Wells setting off the accelerator created all the metahumans, and the results of the singularity will also have long-term effects."

Those ripple effects will still be felt during this upcoming season, as the finale from last year altered the timeline yet again. Now, Eobard Thawne was never born, Harrison Wells was never killed and the Reverse Flash never existed. Well, until a new Reverse Flash known as Professor Zoom shows up, that is.

There were also hints during the finale of other realities that may, or may not, come to pass, such as Caitlin Snow turning into Killer Frost, the Flash Museum being built and Barry in a prison jumpsuit. All of these realities are possible but nowhere near definite — as with all manner of reality in The Flash, anything can change.

Adding even more reality-bending madness to the show, there’s also the time-traveling smooth-talker Rip Hunter now in the mix, as well as the characters from The CW’s next DC series, Legends of Tomorrow.

This series jumps full-on into the timestream, as characters like the Atom, Hawkgirl and Captain Cold travel through the past and the future to stop the immortal bearded villain Vandal Savage from conquering the world. As the CW has shown in recent years, you can expect this series to collide with The Flash throughout the season as DC’s small screen multiverse gets fleshed out further than anyone could have predicted.

This means that Legends of Tomorrow can, in theory, make huge changes to the timeline on The Flash, resulting in a twisting, turning narrative intertwined between the series and giving fans a glimpse of different realities and dimensions nearly every week.

Somewhere in Scotland, Grant Morrison leans back in his custom Mobius Chair, nodding in approval.

How It Ties Together

Confused yet? You should be. Much like DC’s comic book lore, The Flash is always going to run the risk of making itself inaccessible to certain audience members, especially those not invested enough to always have a map of the DC multiverse handy at all times:

Got all that? Didn't think so.

Thankfully, though, the series avoided too much confusion during season 1 by taking some of the most outlandish ideas from the comics and distilling them down to their most important, and entertaining, bits. However, as more convoluted bits of comic book madness get added this year, The Flash might require a DC Universe encyclopedia just to fully grasp the opening credits.

It remains to be seen just how the new episodes will balance all of these heady concepts, especially as even more new characters, like eventual speedster Wally West, get introduced.

We'll know for sure when The Flash begins anew on October 6. 

Be sure to follow T-Lounge on Twitter and visit our Facebook page.