The Best Episodes Written By Greg Berlanti

Douglas discovers Elaine has plans to run for office again as T.J. revisits his old habits and hits rock bottom. Elaine has Bud negotiate for the lives of Iranian hostages, placing him back into the spotlight.

Andy and Ephram's fragile relationship is further strained when it appears that Andy is once again putting work before family. Meanwhile, as the town of Everwood celebrates its annual Fall Thaw Festival, Ephram's interest in Amy continues to blossom. Although Bright tells Ephram that Amy is using him just go get his father to get Colin out of coma. Delia gets into trouble at school for questioning her teacher's antiquated rules.

Nora organizes an engagement party for Kitty and Robert. Justin is about to be deployed to Iraq, and he tries to have special time with his family members to say goodbye. Kitty finds it hard to tell her mother that she will be moving out. An old friend of Saul's visits after his divorce.

Wells presents Barry with a life-changing choice. Dr. Martin Stein and Ronnie Raymond return to help the S.T.A.R. Labs team with this final fight.

Oliver and Diggle race to stop the Dark Archer from unleashing his vengeance on The Glades. However, they run into a roadblock after Detective Lance picks up Felicity for questioning. Tommy and Oliver's already tumultuous relationship takes a turn for the worse after Oliver makes a confession about Laurel. After hearing of the danger in The Glades, Thea races to find Roy, inadvertently putting herself directly in the line of fire for Malcolm's devious plan. On the island, Oliver, Slade and Shado are locked in a life-or-death struggle against Fyers as his missiles lock on a full Ferris Air jetliner.

After covering from a near-fatal drug overdose, Oliver begins hallucinating people from his past. Believing he's a liability, Oliver gives the information he has on Cyrus Gold to Quentin... which results in the deaths of several police officers. Meanwhile, Brother Blood captures Roy and uses him as a test subject for his new serum. In the past on the island, Ivo gives Oliver an impossible choice to make.

As Oliver's face off with Slade escalates, his resolve to the no-kill rule is tested. Especially as Slade targets the woman Oliver loves.

A crossover event that began on "The Flash" concludes with Oliver teaming with the Flash to stop a boomerang-wielding killer who plants five bombs in the city that are set to explode at the same time.

When Oliver and his team destroy Slade's centrifuge, he attacks them as Deathstroke to get what he needs to find a replacement. Meanwhile, Laurel ponders what to do with Slade's information, and Oliver tries to convince Thea to help him protect their finances from Isabel.

When a superhumanly strong thief robs a Queen Consolidated warehouse, Central City police scientist Barry Allen comes to Starling City to investigate the case. However, despite his close working relationship with Felicity, Oliver suspects that there's more to the young scientist than meets the eye. Meanwhile, Sin asks Roy to help investigate the disappearance of a friend. In the past, Oliver, Shado, and Sara try to get Slade to the submarine so they can use the serum to save his life.

Vandal Savage arrives in Central City and sets his sights on Kendra Saunders. After Vandal attacks Kendra and Cisco, they turn to Barry for help. Realizing how dangerous Vandal is, Barry takes Kendra to Star City and asks Oliver and team to hide her until he can figure out how to stop Vandal. However, things quickly go from bad to worse when a man with wings AKA Hawkman shows up and flies off with Kendra. Meanwhile, Harrison develops a serum to make Barry run faster and asks Jay to test it out. The crossover continues on Arrow S04E08 Legends of Yesterday (II).

Barry, Wells and Cisco journey to Earth-2 to rescue Wells’ daughter, Jesse from Zoom. Barry is stunned when he runs into Earth-2 Iris and Joe, but nothing prepares him for meeting Killer Frost and Deathstorm. Meanwhile, back on Earth-1, Jay has to take over the Flash’s responsibilities when a meta-human nicknamed Geomancer attacks Central City.

Approaching the anniversary of his mother's death, Ephram confronts a repressed memory of his father cheating on his mother, causing an even bigger rift between father and son that eventually leads to a firestorm of emotions. Meanwhile, Amy grows concerned that Colin might not be recovering as well as everyone thinks when he gets violently ill on one of their dates. Amy tells her father who later tells Doctor Brown which causes the Harts to dismiss Andy from being their family doctor and causes a feud between Amy and her father.

Abby and Chris find an anonymous note at school. Abby realizes the author and intended recipient had sex the night before and in true Abby fashion, she sets to expose the affair. Working from clues about Joey's night of nude sketching with Jack, Dawson's steamy stop over at Jen's and Pacey's bed and breakfast trip with Andie. Abby calls together her list of suspects and reveals the dirty secrets of Capeside.

Pacey and Joey return from their summer vacation on "True Love". Now they have to deal with Dawson's feelings, who has been deeply hurt for the past months. At first, he doesn't want to talk with neither one of them, but Jen convinces him to talk to Joey. Meanwhile, Pacey's older sister, Gretchen, arrives in Capeside and moves in with Doug, making Pacey homeless. But he won't live with his parents anymore, and so he asks Joey to let him crash at her house for a while. Dawson tells Jack about Gretchen, for whom he had a secret crush a few years ago. Andie meets 2 foreign guys, and she is attracted to them. Dawson and Joey talk, and he says he'll be ok, but it takes one day at a time. Everybody is wondering if Pacey and Joey did it while on the trip, and they don't confirm or deny. But Joey secretly tells Dawson nothing really happened.

Stephen is determined to uncover what he hopes is the key to finding his father, and crafts a plan with the Tomorrow People that involves getting inside Jedikiah's head. Meanwhile, Cara and Russell encounter an uninvited visitor in the subway tunnel base. Stephen takes a risky opportunity and snoops around Ultra.

Barry is thrilled when Oliver, Felicity and Diggle come to Central City to investigate a case involving a deadly boomerang. The crossover continues on Arrow S03E08 The Brave and the Bold.

Diggle and Felicity travel to the island of Lian Yu in search of Oliver, who left Starling City after the devastation of The Undertaking and his failure to avert it. Convinced to return home, Oliver finds that things are in much worse shape than he imagined – Isabel Rochev is preparing a hostile takeover of Queen Consolidated, Thea refuses to visit Moira in jail, Roy is trying to fill the void left by the Arrow's absence, and Laurel is working with the District Attorney's office to take down the vigilante. Meanwhile, flashbacks to the island show Oliver's mentors Slade, Shado and Oliver in a desperate situation.

A charming first encounter quickly turns into something more nefarious when bookstore manager Joe takes a very strong liking to grad student Beck.

After Oliver is shot, he turns to a surprising person for help - Felicity. Diggle is stunned when he sees Felicity walk through the front door of the lair dragging a dying Oliver behind her, and the two team up to save Oliver's life. As Oliver hovers between life and death, he flashes back to a seminal event on the island - a daring escape attempt with his new friend Slade Wilson.

When John finds himself in a dangerous situation, Stephen is unable to help without revealing himself to Ultra. Not satisfied with the answer he has discovered about his father's disappearance, Stephen decides to take drastic measures with the help of his fellow Tomorrow People to find out the truth. Meanwhile, Cara and Russell negotiate a trade with Jedikiah, which ultimately makes Jedikiah take a big risk.

Oliver and Barry Allen take Kendra Saunders and Carter Hall to a remote location to keep them hidden from Vandal Savage while they figure out how to defeat him. Malcolm arranges a meeting between Vandal, Green Arrow and The Flash that doesn’t go as planned. Meanwhile, Felicity, Thea, Diggle and Laurel work with Team Flash to come up with a weapon powerful enough to destroy Vandal Savage. The crossover starts on The Flash S02E08 Legends of Today (I).

After Zoom unleashes an army of Earth-2 meta-humans on Central City, Barry is shaken when he sees their leader is the Black Canary’s Earth-2 doppelganger, the Black Siren. Meanwhile, Wally takes to the streets to help The Flash stop the meta-humans, which worries Joe. Iris and Henry are concerned about Barry taking on Zoom.

Oliver discovers that after he and his father went missing, Moira and Thea stopped celebrating Christmas. Determined to make up for lost time and restore a sense of normalcy to the Queen household, Oliver decides to throw the family a Christmas party. Meanwhile, Tommy asks Laurel to spend Christmas with him but she points out that Christmas was also her sister Sara's birthday and she needs to be with her father. Tommy suggests changing things up might be the best way for everyone to heal but Laurel isn't sure her father is ready for that. Meanwhile, Diggle tells Oliver someone is murdering the people on his father's list with arrows, which sends Oliver off to face his toughest adversary yet.

After learning the Dominators’ plan for the world, the Legends must work together with The Flash, Supergirl and Green Arrow to kill them once and for all. Meanwhile, Stein figures out, with the help of others, how the team can terminate the Dominators, but is distracted by the aberration he realizes he created in 1987. The crossover starts on Supergirl S02E08 Medusa (I), The Flash S03E08 Invasion! (II) and Arrow S05E08 Invasion! (III).