'The Flash'

Barry Allen (Grant Gustin) watched as everyone died at the hands of Vandal Savage (Casper Crump) during the second half of the “Arrow”-“The Flash” crossover, but was thankfully able to save the day after traveling back through time and changing the events before they happened.

Now that he’s saved all of Central City and reversed the deaths of his friends, what will the repercussions be?

Surely there’s bound to be some backlash. The last time Barry accidentally went back in time and changed events, a man died. With the stakes being that he saved so many people, chances are they’re going to be a lot bigger — and stretch all the way to “Arrow.”

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“Any of these things that feel like the right thing to do, there’s always a price to be paid,” executive producer Andrew Kreisberg says at a media screening of the crossover. “Whether or not that price gets paid immediately or whether that price gets paid later on in ways you don’t foresee, it always comes back to haunt you.”

He continues, “When people die, the universe wants them to stay dead and anytime you change that has a cost.”

That’s where the importance of “Legends of Tomorrow” comes in, being that it’s based firmly in a world where time travel is part of everyday life.

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“On ‘Legends,’ Vandal is the big bad, but truly the big bad is time itself. Time wants to go in one direction,” Kreisberg says. “As much as these powers and abilities and technology they have, there is always a price to be paid for using them.”

With a price to be paid, the question now becomes who will pay it?

Posted by:Chris E. Hayner

Chris E. Hayner is equal parts nerd, crazy person and coffee. He watches too much TV, knows more about pro wrestling than you do and remembers every single show from the TGIF lineup. You may have seen him as a pro-shark protester in "Sharknado 3." His eventual memoir will be called "You're Wrong, Here's Why..." TV words to live by: "I'm a firm believer that sometimes it's right to do the wrong thing."