SPOILER WARNING: This article contains major spoilers for “The Trial of The Flash,” the midseason premiere of The Flash Season 4.
In the midseason premiere of The Flash, Grant Gustin's Scarlet Speedster loosely follows in the footsteps of one of his comic book counterpart's most iconic storylines, in the aptly titled episode "The Trial of The Flash." However, before he was sentenced to life in prison for the murder of Clifford DeVoe, Barry Allen had to save Central City from the unwitting radioactive metahuman Fallout.
After using his super-speed to create a vacuum to contain Fallout’s radiation, Barry is left with the dilemma of where to send the toxic emissions. Harry, thanks to his vast knowledge of the Multiverse, quickly realizes the simple answer is to send it to Earth-15, which he says is a “dead Earth,” and with a little help from Cisco’s vibing abilities, that’s exactly what Flash does.
Is Earth-15 really “dead,” though?
First appearing in Countdown #30 by Paul Dini, Justin Gray, Jimmy Palmiotti, Keith Giffen and Jesús Saíz, Earth-15 was one of the 52 Earths that make up the DC Comics Multiverse. It was once known as The Perfect Universe because it was home to heroes who had evolved to become nigh-ideal beings, with many legacy characters, such as Jason Todd, Donna Troy and Kyle Rayner, assuming the mantles of their mentors. However, in the search for his home dimension of Earth-Prime, Superboy-Prime (now dubbed Superman-Prime) killed Earth-15’s version of the Justice League, along with most of the other heroes of that world.
After the events of Flashpoint, which reshaped the fabric of the Multiverse, Earth-15 was effectively replaced by Earth 15 (no hyphen). This version, however, was far from perfect. In fact, it was considered to be a graveyard universe, completely devoid of life. All that remained of this dimension was the mysterious Cosmic Grail, a Green Lantern power battery-type of device, which is lost somewhere in the Multiverse.
Before it became a distant memory, though, Earth 15 was the homeworld of Volthoom, the First Lantern. In the year 3079, upon learning that the planet was destined to be destroyed, Volthoom created the Travel Lantern in the hopes that he could travel through the Multiverse to find a way to save his home.
He eventually arrived on Earth 0, 10 billion years in the past in the lab of Krona, right around the time that the Maltusians conducted an experiment to witness the beginning of all existence, effectively creating the Multiverse and the Antimatter Universe in the process. It was here that the very first Power Ring was created, which Volthoom quickly claimed for himself, granting him a divine connection to the Emotional Spectrum.
Years later, Rami would discover that it was actually Volthoom, himself, who was ultimately responsible for the destruction of Earth 15. However, Volthoom believed Rami merely told him this in an attempt to claim the Power Ring, causing him to go on a murderous rampage. Meanwhile, Rami destroyed the Travel Lantern to prevent Volthoom from returning to/destroying his homeworld and then used the fragments to create the first Green Lantern rings.
With all this in mind, it would seem that the very existence – or lack thereof – of Earth 15 is somewhat paradoxical in nature. Is it actually “dead,” though? Perhaps we’ll need to wait for a new Multiversity Guidebook before we find out for sure.
Airing Tuesdays at 8 pm ET/PT on The CW, The Flash stars Grant Gustin as Barry Allen, Carlos Valdes as Cisco Ramon, Danielle Panabaker as Caitlin Snow, Candice Patton as Iris West, Jesse L. Martin as Joe West, with guest appearances from Keiynan Lonsdale as Wally West and Hartley Sawyer as the Elongated Man.