The CW Network brought its hit superhero shows Arrow and The Flash to PaleyFest over the weekend, where fans were shown sizzle reels for each show that tease the remaining episodes. The Flash sizzle reel previews yet another Arrow crossover, with Atom (Brandon Routh) and Black Canary (Katie Cassidy) popping up in Central City, as Barry tries to put an end to Reverse Flash's reign of terror once and for all. The video also shows returning villains Captain Cold (Wentworth Miller) andHeat Wave (Dominic Purcell).

The Flash returns with "Out of Time" on Tuesday, March 17, which introduces us to Mark Mardon aka The Weather Wizard (guest star Liam McIntyre), who appears in Central City intent on avenging his brother Clyde's death, and sets his sights on Joe, who shot Clyde. When Mardon attacks Joe and Barry, Barry is able to super-speed them to safety but Mardon gets away. Barry warns Joe not to go after a meta-human alone but Joe doesn't listen and ends up in grave danger. Meanwhile, Cisco looks into the night the team captured the Reverse Flash and realizes something doesn't add up and begins to wonder whether Joe was right about Dr. Wells. Barry and Linda (guest star Malese Jow) end up on an awkward double date with Eddie and Iris.

The Arrow sizzle reel finds Ray Palmer finally learning that Oliver Queen (Stephen Amell) is the Arrow, while we also get a brief glimpse at Black Canary being saved by Oliver. There is also a very intriguing revelation that Oliver may become Ra's Al Ghul, after he survived his fight with the villain. The show returns with "The Offer" on Wednesday, March 18, where Oliver is still mulling Ra's al Ghul's (Matthew Nable) offer to join the League of Assassins. Oliver returns home to find a new villain and his crew have started terrorizing Starling City - Michael Amar AKA Murmur (guest star Adrian Glynn Mcmorran), a man whose mouth has been sewn shut. Take a look at these sizzle reels below, before both Arrow and The Flash return this week.

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