Season 4 (Arrow)

The fourth season of Arrow premiered on October 7, 2015 on The CW. It took place in conjunction with the second season of The Flash, and the first season of DC's Legends of Tomorrow.

Official synopsis
''After defeating his most formidable foe to date and riding off into the sunset with longtime flame Felicity Smoak, Oliver Queen (a.k.a. The Arrow) left Starling City with the hopes of beginning a new life. But will Oliver ever truly be able to leave behind his past as the Arrow, and, if so, what becomes of the team he has worked so hard to assemble? Will Diggle, Thea, and Laurel be left to continue Oliver’s crusade without him? And with Malcolm Merlyn having ascended to the top of the League of Assassins as the new Ra's al Ghul, is anyone really safe?''

Main cast

 * Stephen Amell as Oliver Queen/Green Arrow
 * Katie Cassidy as Laurel Lance/Black Canary
 * David Ramsey as John Diggle/Spartan
 * Willa Holland as Thea Queen/Speedy
 * Emily Bett Rickards as Felicity Smoak/Overwatch
 * John Barrowman as Malcolm Merlyn/Dark Archer/Ra's al Ghul
 * Paul Blackthorne as Captain Quentin Lance/Detective

Recurring cast

 * Neal McDonough as Damien Darhk
 * Echo Kellum as Curtis Holt
 * Elysia Rotaru as Taiana Venediktov
 * Jimmy Akingbola as Baron Reiter
 * Ryan Robbins as Conklin
 * Charlotte Ross as Donna Smoak
 * Janet Kidder as Ruvé Adams
 * Eugene Byrd as Andy Diggle
 * Parker Young as Alex Davis
 * Grant Gustin as Barry Allen/The Flash
 * Caity Lotz as Sara Lance/The Canary
 * Brandon Routh as Ray Palmer/The Atom
 * Adrian Glynn McMorran as Michael Amar/Murmur
 * Audrey Marie Anderson as Lyla Michaels
 * Katrina Law as Nyssa al Ghul/Ra's al Ghul
 * Tom Amandes as Noah Kuttler/The Calculator
 * Alexander Calvert as Lonnie Machine/Anarky
 * Cynthia Addai-Robinson as Amanda Waller
 * Natasha Gayle as Mesi Natifah/Talibah

Trivia

 * This is the first season of Arrow that Colin Donnell doesn't reprise his role as Tommy Merlyn, as well as Manu Bennett as Slade Wilson (though Deathstroke does briefly appear as a hallucination)
 * This is the second season where the main antagonist is killed, at least in one timeline.
 * This is the third season to have a main character killed off.
 * Like Season 3, reception for the season finale and much of the season itself was largely negative.
 * Laurel's death has received almost universal backlash from fans and has been the subject of much controversy among critics.
 * Most of the season's criticism has been focused around Felicity and the Smoak family, some action sequences, and few episodes claimed to have bad writing, among other issues.
 * Most of this season's praise has been focused on the first nine episodes and the first half of "Eleven-Fifty-Nine", a few of the action sequences (particularly in "Brotherhood"), the improvement of the characters of Laurel Lance and Thea Queen, the addition of Curtis Holt, and the acting (particularly that of Paul Blackthorne, David Ramsey, Katie Cassidy and Willa Holland).