"Starling City," the season 8 premiere episode of Arrow, revealed some startling differences between the realities of Earth-1 and Earth-2. This proved surprising because, while the episode was obviously set somewhere other than Oliver Queen's homeworld of Earth-1, it was not immediately clear that he was on Earth-2.

While the concept of the Arrowverse was first revealed through the existence of Earth-2 on The Flash, the alternate Earth would come to be important to the story of Arrow as well. This was chiefly due to Black Siren, the Laurel Lance of Earth-2, who was introduced in The Flash as one of the lieutenants of the speedster tyrant and supervillain gang leader Zoom. Contained within STAR Labs' Pipeline prison, she escaped to menace Star City on Earth-1 as a minion of three different supervillains, before finally trying to find redemption as Earth-2's Black Canary.

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The events of Arrow's season 8 premiere saw Oliver Queen transported to Lian Yu on Earth-2, forcing him to make a rather big show of returning home in order to accomplish his mission; retrieving dwarf star particles on behalf of the Monitor. This led to an awkward yet bittersweet homecoming, as Oliver discovered that his mother and his best friend, Tommy Merlyn, were both still alive on this Earth. This would be the first of many disturbing revelations about Earth-2 that Oliver would uncover over the course of the episode. Here is our rundown of all the differences between Earth-1 and Earth-2 revealed in "Starling City".

Oliver Queen's Hometown Is Still Starling City In 2019

Arrow Starling City

The title of Arrow's season 8 premiere turned out to be a reference to one of the key differences of Earth-1 and Earth-2; Oliver Queen's hometown on Earth-2 is still called Starling City in 2019. On Earth-1, the city shortened its name to Star City in honor of Dr. Raymond Palmer (Brandon Routh) and his Star City initiative to rebrand the city. This occurred following Palmer's apparent death in 2015.

It seems likely that the reason for this change is that Earth-2's Ray Palmer never attained the same level of local fame that he possessed on Earth-1 after buying Queen Consolidated. While it is unclear if Ray Palmer existed on Earth-2, it is obvious that he hadn't been as successful as is Earth-1 counterpart if he did. This was revealed when it is shown that Queen Consolidated was just now experimenting with dwarf star matter to develop an alternative fuel source in 2019, whereas Earth-1 Ray had built his ATOM suit using the same material in 2014.

A Batman Mask On Lian Yu

Arrow Season 8 Batman Mask On Lian Yu

The first scene of "Starling City" was a call-back to the pilot episode of Arrow, as Oliver Queen ran across the island of Lian Yu to trigger an explosive signal fire and summon help from a passing ship. As he ran, we saw a mask on a stake with an arrow through the eye socket, but this time the mask is that of Batman (or Batwoman?). On Earth-1, the mask belonged to Deathstroke. This is the first sign that Oliver Queen is on another Earth and that the world of this episode will be very different.

RELATED: Arrow: Why Batman’s Mask Replaced Deathstroke’s In Season 8

Earth 2's Oliver Queen Is Dead

Stephen Amell as Oliver Queen in Arrow

A news report in The Flash, season 2, episode 6, "Enter Zoom," confirmed that Earth-2's Oliver Queen truly was lost at sea and that his father, Robert Queen, returned to civilization to become the vigilante known as "The Hood." "Starling City" made reference to part of this, with Oliver being said to have returned home after 12 years of being presumed dead. However, "Starling City" said nothing about Robert Queen's fate on this Earth.

Malcolm Merlyn & Moira Queen Remarried

Arrow Season 8 Malcom Merlyn and Moira Queen

The question of what happened to Robert Queen became important in light of the first shocking change that Oliver discovered upon his return to Starling City; his mother, Moira Queen, had remarried Malcolm Merlyn instead of Robert Queen's former business partner, Walter Steele. The two likewise merged their companies together into Queen-Merlyn Consolidated. This would seem to ignore the revelation from The Flash that Robert Queen became a vigilante on Earth-2 and had his identity exposed to the world.

It is possible that this still happened, but that Moira divorced her first husband after he was arrested and his secret identity was exposed in 2015, clearing the way for her to marry Malcolm. It's also possible that this is a continuity hiccup caused by Barry Allen's altering the timeline or traveling between Earths. In any case, it is still incredibly awkward for Oliver to see his mother married to one of his greatest enemies on Earth-1, even though the Earth-2 version of Malcolm Merlyn is a good man by all accounts.

Thea Died Of A Drug Overdose On Her 18th Birthday

Arrow Willa Holland as Thea Queen

After being welcomed home by his best friend, Tommy Merlyn, Oliver was quick to ask why his sister Thea Queen wasn't there. After an awkward silence, Moira told Oliver that Thea died of a drug overdose on her 18th birthday. This would seem to be an alternate take on the events of the season 1 Arrow episode "Trust, But Verify," where the Earth-1 Thea Queen crashed her brand new car after her 18th birthday party, while high on the effects of the party drug Vertigo.

RELATED: Arrow Rewrites Season 1 On Black Canary's Earth By Killing [SPOILER]

Adrian Chase is The Hood

Adrian Chase looking shocked in Arrow

When Oliver broke into the lab containing the dwarf star particles he needed, he found several dead bodies full of arrows and an enraged man wearing his costume. The two fought only to be broken up by Laurel, who demanded an explanation, as the other hooded man revealed himself to be the Earth-2 version of the man Oliver knew as Adrian Chase/Prometheus. According to Laurel, the Earth-2 version of Adrian Chase was a good man, who took up the Hood identity to help her protect Starling City. It was not explained, however, why he used the name Adrian Chase when Prometheus' real name on Earth-1 was Simon Morrison and he used Adrian Chase as an alias to get close to Oliver Queen (whom he blamed for killing his father) undetected.

Felicity Smoak Is Running Her Own Company

Arrow Season 8 Starling City Fake Felicity

When Oliver later infiltrated Queen-Merlyn Consolidated as himself, he couldn't help but swing by the IT Department in the hopes of seeing the Earth-2 version of his wife, Felicity Smoak. Instead, Oliver found a remarkably similar woman with blonde hair and glasses sitting at what was Felicity's desk on Earth-1. When Oliver asked where Felicity Smoak was, the woman laughed at the idea of someone as rich and powerful as Felicity Smoak slumming it in IT and revealed that Earth-2's Felicity Smoak was the head of a company called Smoak Tech. This gels with a statement made by Earth-2's Laurel Lance in the season 7 Arrow episode "Level Two", where she told Earth-1's Felicity that her doppelganger was a tech magnate known for being crafty and ruthless in her business dealings.

Curtis Holt Runs Queen-Merlyn's IT Department

Arrow Season 8 Curtis Holt And Husband

With his side quest to steal a look at his wife's doppelganger a bust, Oliver got back to business and asked the Felicity lookalike where he could find the office of the person who was in charge of the company's IT department. As Oliver snuck into the office and started hacking the computer, we saw a framed picture of a young couple on the desk. It was here that we learned that the IT manager is the Earth-2 version of Curtis Holt, aka Earth-1's Mister Terrific.

Dinah Drake and Rene Ramirez Work For The Dark Archer

Arrow Season 8 Dinah Drake and Rene Ramirez

Oliver ran into two more familiar faces after an encounter with the Dark Archer in Malcolm Merlyn's office. Dinah Drake was the SCPD Detective Sergeant summoned to take Malcolm's statement as to why two hooded archers were trying to kill him. She was escorted off the premises of Queen Manor by Rene Ramirez, who was employed as Malcolm's personal bodyguard. On Earth-1, the two were among Oliver Queen's closest allies as the vigilantes Black Canary and Wild Dog. Their Earth-2 counterparts, however, were revealed to be in league with the Dark Archer and nowhere near as well-trained in fighting as their Earth-1 doppelgangers.

RELATED: Arrow Season 8 Cast & Character Guide

Tommy Merlyn Is The Dark Archer

Arrow Season 8 Earth 2 Tommy Merlyn is Dark Archer

The changes to Tommy Merlyn on Earth-2 were ultimately revealed to go far beyond his getting married and divorced twice over the 12 years since Oliver Queen disappeared. In this reality, inspired by Thea's death, Tommy became obsessed with destroying the Glades; the biggest slum in Starling City, which he blamed for corrupting his sister and causing her death. While it was not explained how Tommy gained the combat skills needed to match Oliver Queen in battle, this plot mirrored that of Earth-1's Dark Archer, Malcolm Merlyn. '

In Arrow's first season, the elder Merlyn also plotted to destroy the Glades after his beloved wife was killed during a mugging. The other key difference between their plans was that Malcolm's Undertaking utilized an earthquake generator whereas Tommy constructed a doomsday device using dwarf star particles.

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