Felicity learns that Ray (Brandon Routh) is alive and is being held captive by Damien Darhk (Neal McDonough); effects of the Lazarus Pit could jeopardize the mission to rescue Ray.

Oliver calls in a favor from an old friend, John Constantine (Matt Ryan), when things with Sara take a turn for the worse.

Laurel faces the consequences of her actions; when Oliver turns to Lance for a favor, he is surprised by what he learns.

The tension between Oliver and Diggle puts them at risk when they target Damien Darhk and a meta-human; Laurel convinces Thea to return to Nanda Parbat to request Sara be put into the Lazarus Pit.

Oliver and Thea are concerned when a family friend plans to run for mayor; Thea starts to exhibit side effects from the Lazarus Pit; Felicity asks an employee for help with a business decision.

Oliver and Felicity's blissful getaway comes to an abrupt end when Laurel and Thea ask for their help; Diggle is opposed to working with Oliver.

Ra's al Ghul sets his plan in motion, putting everyone in danger; Oliver must decide if he is strong enough to handle his new role -- and what it will mean for his team and his soul.

Oliver must complete two final tasks before coming the next Ra's al Ghul; Nyssa is threatened; Malcolm makes an offer to the team; Thea visits Roy.

Oliver goes through a transformation; Laurel asks Felicity and Diggle to help Nyssa face the League of Assassins.

Ra's al Ghul presents Oliver with an irresistible offer; Felicity takes matters into her own hands as the team accompanies Oliver on a journey.

With Lance still targeting the Arrow, Felicity insists that Oliver keep a low profile; a metahuman who uses blasts of energy and plasma to kill people terrorizes the city, forcing Ray and Oliver to team up.

Ray is seriously injured when the mayor's office is attacked; Felicity's mother visits to offer support; Oliver and the team's pursuit of the person responsible becomes complicated when Capt. Lance is kidnapped by Ra's al Ghul.

Diggle and Lyla's honeymoon is interrupted by the Suicide Squad and a new mission; Oliver and Ray have a heated confrontation about the Atom costume, leading to a rough patch between Ray and Felicity.

Oliver learns a new villain and his crew have been terrorizing Starling City; Nyssa and Laurel bond over their issues; Lance shuts out the Arrow and Laurel.

Ra's al Ghul captures Malcolm and takes him to Nanda Parbat; Ray obsesses over finishing his Atom suit, but Felicity tries to get him out of the lab to prevent him from going down the wrong path.

Malcolm places Oliver and Thea in a dangerous situation; a flashback reveals a time when Oliver and Maseo returned to Starling City.

Oliver struggles to adjust to the changes that have taken place within Team Arrow; Laurel ignores Oliver and pursues Vertigo -- who injects her with the drug; Thea receives a surprise visitor.

Still without Oliver, the team is forced to consider Malcolm's offer; more details of Malcolm's life are revealed.

Diggle and Arsenal confront Laurel about her dangerous work as the Black Canary; Felicity sees a new side of Ray as he helps Lance fight a villain who has kidnapped the city's Aldermen.

As Diggle, Felicity and Roy start to fear the worst after Oliver's disappearance, Merlyn pays them a surprise visit; Ray experiments with part of his new suit; Laurel takes on the role of the Black Canary.

Laurel is surprised when her father shows up with a with a special Christmas gift -- her mother, Dinah; Ray tries to make things right with Felicity; Oliver meets with Ra's al Ghul.

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.

"Arrow" and "The Flash" have some new superhero company in the CW's lineup with the addition of "DC's Legends of Tomorrow." After seeing what doom the future holds, time-traveling rogue Rip Hunter realizes heroes alone are not enough to prevent the impending catastrophe that threatens not only the planet, but all of time itself. Tasked with recruiting both heroes and villains, Rip brings together a ragtag team of divergent talents, which includes the likes of Sara Lance, Ray Palmer, and Heat Wave.

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.

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.