The series premiered in the United States on The CW on October 10, 2012, with international broadcasting taking place in late 2012 and primarily filmed in Vancouver, British Columbia, Canada.
Starting with season seven, a series of flash-forwards focus on Oliver's children William and Mia, exploring how present events would affect their future and Green Arrow's legacy.
Michael Amar / Murmur (portrayed by Adrian Glynn McMorran[5]) is a man whose mouth is sewn shut, who enacts a deadly revenge scheme on the Starling City police for imprisoning him in Iron Heights Penitentiary on a false confession.
[14] He is later summoned by John Diggle to pose as Tommy Merlyn in Green Arrow's costume during Oliver Queen's trial and later takes the place of Judge C. McGarvey.
In "Taken", a primordial energy takes the form of Conklin and stands at the entrance of the cave, speaking in tongues, but disappears when it notices the spell tattoo on Oliver's chest and deemed him worthy to pass.
[25] Jessica Danforth (portrayed by Jeri Ryan) is a friend of the Queen family[26] and mayoral candidate for Star City[27] who drops out of the race after her daughter's kidnapping.
Kara Danvers / Supergirl (portrayed by Melissa Benoist)[30] is Barry Allen's friend and ally from another universe, whom Oliver also ultimately befriends during an alien invasion crisis.
In season four, he is introduced as the main antagonist, a formidable hand-to-hand combatant with mystical abilities—he can remotely manipulate objects and people, and can drain the life force from a person through physical contact.
Diggle and Michaels originally had a daughter named Sara, but Barry Allen's time traveling and creation (and subsequent erasure) of the Flashpoint timeline results in her being replaced by J.J.[38] Keon Boateng and Marcello Guede portray J.J. as a child from season five to seven.
Ted Gaynor (portrayed by Ben Browder) is Diggle's former military commander who turns rogue and starts robbing cash from truck transfers only to be killed by the Arrow.
Nyssa feels betrayed when Raʾs declares Oliver his successor and releases Malcolm, and she leaves Nanda Parbat for Starling City and begins training Laurel.
'The Demon's Head'; portrayed by Matt Nable) is the main antagonist of season three and leader of the League of Assassins who has lived for at least two centuries (having been born some decades before 1854) due to the use of the Lazarus Pit, a pool which can heal wounds and bring the dead back to life.
With Black Siren now under his employment, James and his followers Ricardo Diaz, Vincent Sobel, Anatoly Knyazev, and Sheck are in the process of working on their latest unknown project known as Arclight.
Noah Kuttler / Calculator (portrayed by Tom Amandes) is Felicity's long-lost father, who is a career cyber-criminal whom Donna Smoak divorced from eighteen years previously.
In season four, Laurel, Thea, and Malcolm resurrect Sara using the Lazarus Pit, but she returns mentally fractured until Oliver brings in his old friend John Constantine to help restore her soul.
Ray Palmer / Atom (portrayed by Brandon Routh) is a scientist, inventor, minister and businessman who succeeds Isabel Rochev as CEO of Queen Consolidated after her crimes are posthumously exposed.
After his fiancée, Anna Loring, is killed by one of Slade Wilson's Mirakuru soldiers, Ray uses the company's research and technical inventions to develop a suit powered by white dwarf matter, which, in his theory, can alter the wearer's size down to the subatomic level.
In the season finale Ray is working on the suit with the intention of giving it the power to shrink but a malfunction causes the entire top floor of Palmer Technologies to blow up.
When Oliver Queen is impeached as mayor and later arrested as well as his successor Quentin Lance dying during surgery following the fight against Ricardo Diaz, Pollard takes his place and implements her measures with a firm hand.
As a young man, Robert gained his wealth through corrupted means; he gradually become remorseful of his greed, leading him to join Malcolm's secret society, Tempest, to improve Starling City's condition in hope of making amends.
Rory Regan / Ragman (portrayed by Joe Dinicol) arrives "fresh from a personal tragedy" hoping to find answers in Star City, where he ultimately crosses paths with Green Arrow.
Baron Reiter (portrayed by Jimmy Akingbola)[100][101] is the leader of Shadowspire in the season four's flashbacks,[20] when he was searching for magical artifacts on Lian Yu, specifically the idol that Damien Darhk later possesses.
Evelyn Crawford Sharp (portrayed by Madison McLaughlin) is a woman who takes up the mantle of the Black Canary following Laurel's death, eventually settling on the name Artemis.
Jake Simmons / Deathbolt (portrayed by Doug Jones) is a metahuman from Opal City who receives his powers through unknown means, with the ability to harness and weaponize plasma energy.
[122] David Singh (portrayed by Patrick Sabongui) is the Central City Police Captain who provided the Green Arrow and his team with information that lead to the location of Dinah Drake.
Donna and Quentin eventually end up getting married in the season seven finale, we later find out she gets pregnant and gives birth to Felicity's younger brother Noah Lance.
He is revealed to be a member of Cayden James' criminal cabal, but is working as a double agent who informs Team Arrow of their activities, primarily because of his love for Dinah.
In the season three flashbacks, she rescues Oliver from Lian Yu after witnessing his progressive skills in combat and forces him to work for her and, in the process, furthers his training two years prior to his return to Starling City.
Alena Whitlock (portrayed by Kacey Rohl) also known as Kojo Sledgehammer,[151] is a member of the Helix hacking organization who attempts to recruit Felicity to their ranks after helping her clear Diggle's name.
He returns in the season eight episode "Purgatory" where Team Arrow and Lyla Michaels encounter Wintergreen, Fyers and his group on Lian Yu when the energy build-up restored them.