IN PHOTO: Cast Member Grant Gustin Attends A Panel For The CW Television Series 'The Flash.'
IN PHOTO: Cast member Grant Gustin attends a panel for The CW television series "The Flash" during the Television Critics Association Cable Summer Press Tour in Beverly Hills, California July 18, 2014. MARIO ANZUONI/Reuters

"The Flash" Season 1, Episode 7, titled "Power Outage," airs Tuesday, Nov. 25, on The CW. This week's new episode opens the story arc that will culminate in a 2-parter crossover with "Arrow." Robert Knepper's William Tockman is going to wreak havoc in Central City, and he comes with a partner villain.

Spoiler alert: This update contains The Flash Season 1 spoilers. Read at your own risk if you have not watched the previous episodes.

William Tockman, aka the Clock King, was a DC Comics villain who was integrated into The CW's "Arrow" adaptation in Season 2. In The Flash Season 1, Episode 7, he goes back to robbing banks and Barry Allen (Grant Gustin) is going to need Oliver Queen's (Stephen Amell) help to beat him and his partner.

Clock King's partner is "Farooq aka Blackout (guest star Michael Reventar), a metahuman who can harness electricity," according to The CW episode synopsis.

In a TV Line report, Arrow and The Flash showrunner Andrew Kreisberg said Barry will fight "both a new enemy [Farooq] and one of our scariest and most successful Arrow villains in The Clock King." Oliver Queen teams up with Barry in Episode 8, but this week's new episode plants seeds for the big crossover, which will conclude in Arrow Season 3, Episode 8 (air date Dec. 3 on The CW).

"During their battle, Farooq zaps The Flash and siphons all his electricity, leaving The Flash without his speed," reads the episode guide for "Power Outage." Farooq storms in at S.T.A.R. Labs, and Barry's friends, including Dr Wells, find themselves in great danger.

The Flash Season 1, Episode 7 was written by Alison Schapker and Grainne Godfree, and directed by Larry Shaw.

Meanwhile, the Reverse Flash has re-appeared in The Flash Season 1, Episode 6, threatening Joe (Jesse L. Martin) that harm will fall on Iris (Candice Patton) if he does not stop his re-investigation into the death of Barry's mother. This happens after Joe apologized to Dr Wells (Tom Cavanagh) for being suspicious of his past.

Eddie (Rick Cosnett) is suspected by viewers to be Eobard Thawne of DC Comics, the Reverse Flash. Eddie has helped Barry calculate his punches in The Flash Episode 6, but so far Iris' boyfriend has done nothing extraordinary. In contrast, Dr Wells, who is faking paralysis, and has committed murder, is becoming more suspicious by each episode.

The Flash airs Tuesdays on The CW. Arrow, now on its third season, airs Wednesdays in the same network.

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