Oliver learns that Malcolm Merlyn is alive -- and thinks he was responsible for Sara's death; Laurel avoids Nyssa, believing that Sara's association with the League of Assassins led to her demise.

When Felicity determines that Thea is in Corto Maltese, Oliver intends to bring her back home; Diggle is double-crossed; Laurel and Ted Grant meet.

Another archer comes to town and targets businessmen; Roy is forced to tell Oliver why Thea left town; Laurel considers sharing a secret with Lance.

With crime at an all-time low, Oliver lets his guard down and is taken by surprise by a new villain; Oliver and Roy take on the Count; Diggle becomes a father; Lance gets a promotion; Laurel joins the inner circle.

Oliver is forced to reconsider what he is willing to do to stop Slade from killing someone else close to him; Diggle goes after Amanda.

As Slade's soldiers target the city, Oliver rallies his team; Felicity receives game-changing news from S.T.A.R. Labs; Thea and her father come face to face.

Diggle and Felicity go to extremes to keep Oliver from surrendering to Slade; Thea thinks about leaving town; Laurel goes after Sebastian Blood again.

When the mirakuru sends Roy into a blind rage, Oliver must find a way to stop him; Thea tries to lure Roy in by going on camera at Moira's campaign.

An epic battle ensues when the team find Slade waiting for them in the lair; Thea reaches her breaking point; Laurel struggles with a secret.

The repercussions are massive when Slade makes a move against Oliver; a key player in Oliver's team starts to question his decisions.

Oliver expects the Huntress (Jessica De Gouw) to return once her father (Jeffrey Nordling) is arrested; Laurel is involved in a hostage situation at the courthouse; Roy tries to keep Thea safe.

Oliver prepares for battle with his former friend Slade; Amanda recruits Diggle to stop a warlord, but he is surprised when he meets the rest of the team she has assembled.

Oliver is stunned when he discovers that Slade is in Starling City; back on the island, Sara and Oliver form a plan to deal with Slade's growing Mirakuru-induced rage.

Felicity feels left out when Oliver makes Sara a part of the team; a brilliant thief known as The Clock King arms himself with technology that can open bank vaults; Laurel refuses to attend a party for Sara.

Lance and Oliver try to talk Sara into reuniting with Laurel, who continues to unravel; Dinah is kidnapped.

Arrow offers to train Roy, but Roy refuses unless Arrow reveals his true identity; Malcolm's earthquake machine is stolen by the Bronze Tiger; Laurel spins out of control after she is disbarred.

Oliver feels conflicted when Laurel asks the Arrow for help investigating Sebastian Blood; Sin wants Roy to test his new super-strength.

Arrow tries to stop a man from setting off a bomb at a rally but gets trapped in the process; Thea witnesses Roy's superstrength and demands answers.

Wild Dog defies the Green Arrow's orders by taking it upon himself to go after drug dealer Garret Runnels, who is terrorizing Star City.

Oliver assembles a group of unlikely allies - Slade, Nyssa, Merlyn and Digger Harkness - to engage in an epic battle against Chase and his army.

Black Siren returns to help Chase; Felicity organizes a birthday party for Oliver; Lance is furious when Rene misses the custody hearing for his daughter.

At 11, Barry Allen's life changed completely when his mother died in a freak accident and his innocent father was convicted of her murder. Now a crime-scene investigator, his dedication to learn the truth about his mother's death drives him to follow up on every new scientific advancement and urban legend. When his latest obsession -- a particle accelerator heralded as a world-changing invention -- causes an explosion, it creates a freak storm and Barry is struck by lightning. He awakes from a coma nine months later with the power of superspeed. When he learns that others who have gained powers use them for evil, he dedicates himself to protecting the innocent, while still trying to solve the older mystery.

At 12 years old, Kara Zor-El escapes doom on planet Krypton to find protection on Earth with the Danver family, where she grows up in the shadow of her foster sister, Alex, and learns to hide the extraordinary powers she shares with her cousin, Superman. Now an adult living in National City and working for media mogul Cat Grant, Kara finds her days of keeping her abilities a secret are over when super-secret agency head Hank Henshaw enlists her to help protect the city's citizens from threats. Finally coming into her own, Kara must juggle her new responsibilities with her very human relationships.

CW and Greg Berlanti expand the footprint of their DC Comics universe with this exploration of the intersection between family life and being a superhero. As a younger man, Jefferson Pierce donned the suit of a vigilante and protected the streets of his city, but he believed he'd left those days in the past. He learns that life doesn't always work out as planned when his daughter, Jennifer -- a star student who is determined to achieve justice at any cost -- gets recruited by a street gang. In order to protect his family, Jefferson sees no choice but to once again become Black Lightning.

Three years after Batman mysteriously disappeared, Gotham is a city in despair, and it's under the watch of Jacob Kane and his military-grade Crows Private Security, which now protects the city with omnipresent firepower and militia. When the Alice in Wonderland gang targets the firm, Kane's daughter Kate returns home, deciding that if she wants to help her family and her city, she'll have to become the one thing her father loathes -- a dark knight vigilante. With the help of her stepsister Mary and the crafty Luke Fox, the son of Wayne Enterprises' tech guru Lucius Fox, Kate Kane continues the legacy of her missing cousin, Bruce Wayne. Armed with a passion for social justice and a flair for speaking her mind, Kate soars through the shadowed streets of Gotham as Batwoman.