<P> The fourth season of the American television series The Flash, which is based on the DC Comics character Barry Allen / Flash, follows a crime scene investigator with superhuman speed who fights criminals, including others who have also gained superhuman abilities . It is set in the Arrowverse, sharing continuity with the other television series of the universe, and is a spin - off of Arrow . The season is produced by Berlanti Productions, Warner Bros. Television, and DC Entertainment, with Andrew Kreisberg and Todd Helbing serving as showrunners . </P> <P> The season was ordered in January 2017, and filming began that July . Grant Gustin stars as Barry, with principal cast members Candice Patton, Danielle Panabaker, Carlos Valdes, Keiynan Lonsdale, Tom Cavanagh, and Jesse L. Martin also returning from previous seasons, and are joined by Neil Sandilands . </P> <P> The fourth season began airing on October 10, 2017, on The CW . </P> <Table> <Tr> <Th> No . overall </Th> <Th> No. in season </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> Prod . code </Th> <Th> U.S. viewers (millions) </Th> </Tr> <Tr> <Th> 70 </Th> <Td> </Td> <Td> "The Flash Reborn" </Td> <Td> Glen Winter </Td> <Td> Story by: Andrew Kreisberg Teleplay by: Todd Helbing & Eric Wallace </Td> <Td> October 10, 2017 (2017 - 10 - 10) </Td> <Td> T27. 13401 </Td> <Td> 2.84 </Td> </Tr> <Tr> <Td_colspan="8"> Iris has been aiding Team Flash in Central City for six months, but refusing to grieve Barry . A flying Samurai with superpowers appears in Central City, threatening to destroy the city if the real Flash does not face him . Cisco reveals he has formulated a way to bring back Barry without destabilizing the Speed Force, and tracks down Caitlin for help . Against Iris' direction, Team Flash successfully returns Barry, who appears rambling random statements and continually writing symbols on walls . Wally engages the Samurai, but is defeated . Cisco deciphers Barry's writings and finds an apparently meaningless sentence . In an attempt to recover Barry's memories, Iris gives herself up to the Samurai . The plan works and Barry speeds away, rescuing Iris and defeating the Samurai, who is revealed to be a robot . Caitlin rejoins Team Flash, but is revealed to have been working for a mobster called Amunet at the bar, while also continuing to prevent the Killer Frost personality from emerging . The "Samuroid" is revealed to have been controlled by the Thinker, whose plan was to draw out the Flash for his next schemes . </Td> </Tr> <Tr> <Th> 71 </Th> <Td> </Td> <Td> "Mixed Signals" </Td> <Td> Alexandra La Roche </Td> <Td> Jonathan Butler & Gabriel Garza </Td> <Td> October 17, 2017 (2017 - 10 - 17) </Td> <Td> T27. 13402 </Td> <Td> 2.54 </Td> </Tr> <Tr> <Td_colspan="8"> When Barry, Joe, and Cisco report to a crime scene, they discover remnants of a mysterious code . Cisco presents Barry with a technologically advanced suit, intended to facilitate his activities . He tests it out, trying to save someone from a haywire car, caused by metahuman Ramsey Deacon . Gypsy arrives on Earth - 1 for a date with Cisco, who is forced to cancel it so as to focus on Deacon . Acting on a suggestion from Caitlin, Iris signs her and Barry up for couples therapy to sort out their relationship . Deacon kidnaps a witness, who was previously a member of a tech team who sold him out of his idea . Barry and Wally go to save him, but Deacon uses his abilities to send Barry's suit haywire . On Iris's instructions, Barry throws lightning at himself, shorting out his suit . He then incapacitates Deacon, who is locked up in the meta wing of Iron Heights, revealed to be part of the Thinker's plan . Cisco finally goes out with Gypsy . Wondering how Deacon gained his powers being absent during the particle accelerator incident, Barry and Joe learn from Deacon that there are "others". </Td> </Tr> <Tr> <Th> 72 </Th> <Td> </Td> <Td> "Luck Be a Lady" </Td> <Td> Armen V. Kevorkian </Td> <Td> Sam Chalsen & Judalina Neira </Td> <Td> October 24, 2017 (2017 - 10 - 24) </Td> <Td> T27. 13403 </Td> <Td> 2.62 </Td> </Tr> <Tr> <Td_colspan="8"> In flashbacks, the Thinker observes Becky Sharpe, a woman with seemingly unending bad luck, and determines that she will be easily manipulated . In the present, Becky robs a bank, and gets away when Barry slips on marbles . Harry arrives from Earth - 2, and tells Wally that Jesse has decided to break up in order to focus on her vigilantism . Cisco deduces that Becky is a metahuman with the power of favorable luck while inducing misfortune to others . Barry realizes that the portal he used to escape the Speed Force exposed an entire busload of people, including Becky and Deacon, to transformative dark matter . Harry informs Cisco that Jesse has expelled him from her crime - fighting team, due to his attitude . Becky's powers expand out of control, reactivating the particle accelerator, which Harry deliberately allows, nullifying Becky's powers and leading to her incarceration . Cisco and Harry identify twelve new metahumans created on the bus, and the latter suspects that an unknown party has manipulated events surrounding Barry's return . Wally decides to leave on a journey to find himself . The Thinker is revealed to be spying on S.T.A.R. Labs through the "Samuroid" helmet . Joe learns Cecile is pregnant . </Td> </Tr> <Tr> <Th> 73 </Th> <Td> </Td> <Td> "Elongated Journey Into Night" </Td> <Td> Tom Cavanagh </Td> <Td> Sterling Gates & Thomas Pound </Td> <Td> October 31, 2017 (2017 - 10 - 31) </Td> <Td> T27. 13404 </Td> <Td> 1.99 </Td> </Tr> <Tr> <Td_colspan="8"> Gypsy's father, Breacher, attacks Cisco, vowing to hunt and kill him in 24 hours, allowing the romance should he survive . Team Flash learns that the bus driver was murdered and tracks down another passenger, Ralph Dibny, former corrupt CCPD detective exposed by Barry and currently an infamous private investigator . As two thugs attack Dibny, he is revealed to have the power to stretch . Caitlin stabilizes his powers with a serum . The team learns that Ralph has been blackmailing Mayor Bellows for adultery, with the latter revealed to have hired the thugs . Barry confronts Ralph for his actions while the latter scolds him, claiming to have been a "good cop". He later stops blackmailing Bellows, who still attempts to kill him while Breacher mistakes the former for a Plastoid, the species that invaded Earth - 19 previously, and attacks him . Cisco intervenes and saves Ralph, whom Barry, having revealed his alter - ego, convinces to help arrest an escaping Bellows . Admiring Cisco's gallantry, Breacher allows the relationship . Barry recruits Ralph for Team Flash and learns that someone named DeVoe instructed Ralph to watch Bellows . Barry remembers that Abra Kadabra and Savitar both mentioned DeVoe . Meanwhile, Caitlin finds a message on her apartment door . </Td> </Tr> <Tr> <Th> 74 </Th> <Td> 5 </Td> <Td> "Girls Night Out" </Td> <Td> Laura Belsey </Td> <Td> Lauren Certo & Kristen Kim </Td> <Td> November 7, 2017 (2017 - 11 - 07) </Td> <Td> TBA </Td> <Td> TBD </Td> </Tr> <Tr> <Th> 75 </Th> <Td> 6 </Td> <Td> "When Harry Met Harry ..." </Td> <Td> Brent Crowell </Td> <Td> Jonathan Butler & Gabriel Garza </Td> <Td> November 14, 2017 (2017 - 11 - 14) </Td> <Td> TBA </Td> <Td> TBD </Td> </Tr> <Tr> <Th> 76 </Th> <Td> 7 </Td> <Td> "Therefore I Am" </Td> <Td> David McWhirter </Td> <Td> Eric Wallace & Thomas Pound </Td> <Td> November 21, 2017 (2017 - 11 - 21) </Td> <Td> TBA </Td> <Td> TBD </Td> </Tr> <Tr> <Th> 77 </Th> <Td> 8 </Td> <Td> TBA </Td> <Td> TBA </Td> <Td> TBA </Td> <Td> November 28, 2017 (2017 - 11 - 28) </Td> <Td> TBA </Td> <Td> TBD </Td> </Tr> <Tr> <Td_colspan="8"> This episode continues the crossover event "Crisis on Earth - X" that will begin on Supergirl season 3 episode 8, followed by Arrow season 6 episode 8 and conclude on Legends of Tomorrow season 3 episode 8 . </Td> </Tr> </Table>

When is season 4 of the flash released