Season 6 (Arrow)

The sixth season of premiered on October 12, 2017, on The CW and concluded on May 17, 2018. The season consisted of 23 total episodes during its run.

Synopsis
After a violent shipwreck, billionaire playboy Oliver Queen was missing and presumed dead for five years before being discovered alive on a remote island in the North China Sea. He returned home to Star City, bent on righting the wrongs done by his family and fighting injustice. As the Green Arrow, he protects his city with the help of former soldier John Diggle, computer-science expert Felicity Smoak, his vigilante-trained sister Thea Queen, Deputy Mayor Quentin Lance, brilliant inventor Curtis Holt, and his new recruits, street-savvy Rene Ramirez and meta-human Dinah Drake. Oliver has finally solidified and strengthened his crime-fighting team only to have it threatened when unexpected enemies from his past return to Star City, forcing Oliver to rethink his relationship with each member of his "family".

Main Cast

 * Stephen Amell as Green Arrow (Oliver Queen)
 * David Ramsey as Spartan (John Diggle)
 * Willa Holland as Speedy (Thea Queen) *
 * Emily Bett Rickards as Overwatch (Felicity Smoak)
 * Echo Kellum as Mister Terrific (Curtis Holt)
 * Rick Gonzalez as Wild Dog (Rene Ramirez)
 * Juliana Harkavy as Black Canary (Dinah Drake)
 * Katie Cassidy as Black Siren (Laurel Lance)
 * Paul Blackthorne as Quentin Lance

Recurring Cast

 * Adrian Holmes as Frank Pike
 * Jack Moore as William Clayton
 * Audrey Marie Anderson as Lyla Michaels
 * Venus Terzo as Dr. Elisa Schwartz
 * David Nykl as Anatoly Knyazev
 * Kacey Rohl as Alena Whitlock
 * Michael Emerson as Cayden James
 * Sydelle Noel as Samanda Watson
 * Kathleen Gati as Raisa
 * Tobias Jelinek as Sheck
 * Johann Urb as Vigilante (Vincent Sobel)
 * Pej Vahdat as Sam Armand
 * Teryl Rothery as Jean Loring
 * Tina Huang as Kimberly Hill
 * Gina Ravera as Lydia Cassamento
 * Kirk Acevedo as Dragon (Ricardo Diaz)
 * Manu Bennett as Deathstroke (Slade Wilson)
 * Colton Haynes as Arsenal (Roy Harper)

In-Universe Guest Stars

 * Grant Gustin as The Flash (Barry Allen)
 * Victor Garber as Firestorm (Martin Stein)
 * Caity Lotz as White Canary (Sara Lance)
 * Tom Cavanagh as Harry Wells / Reverse-Flash/Harrison Wells (Eobard Thawne)
 * Chyler Leigh as Alex Danvers
 * Dominic Purcell as Heat Wave (Mick Rory)
 * Candice Patton as Iris West
 * Franz Drameh as Firestorm (Jefferson Jackson)
 * Danielle Panabaker as Killer Frost (Caitlin Snow)
 * Melissa Benoist as Supergirl (Kara Danvers) / Overgirl (Kara)

Notes:
 * 1) Willa Holland is credited as a series regular through 6x16.