Before "Flash" races back onto television screens tonight with its season two premiere, showrunner and executive producer Andrew Kreisberg spoke with Entertainment Weekly about what to expect in the show's sophomore season -- which will include Earth-2, a new powerset for Barry and a crossover with "Arrow" that will lead to the upcoming spinoff series "Legends of Tomorrow."

When it comes to "Legends," "The Flash" will introduce Hawkgirl (Ciara Renee), a character we briefly saw in the season one finale. "She comes in a little bit under the radar," said Kreisberg. "She is a denizen of Central City, as we saw in the finale, and she is going to slowly get involved with our team in a somewhat surprising way. We'll be introducing her, and also we have Professor Stein, played by the incomparable Victor Garber, who becomes part of the team from the get-go."

This year's "Arrow" crossover will lead into "Legends of Tomorrow," a series that stars supporting characters from both shows. "We're really excited about the crossover. We worked so hard on the crossovers last year, making sure that they were exciting, entertaining and bold. The only way to top it is to go even bigger and even bolder. We're going to be introducing part of the Hawkman (Falk Hentschel) mythology in those episodes, and Kendra will play a big part in those. The crossovers are really going to set the stage for 'Legends,' but in a cool way so that if you don't watch 'Arrow' and 'Flash,' and you didn't see the crossovers, you would still really enjoy 'Legends.'"

Kreisberg spoke about Earth-2, the alternate reality that's home to new cast addition Jay Garrick (Teddy Sears). "Year one was all about time travel. Time travel can be a very tricky concept if done poorly, and we took great strides and worked really hard to make our version of time travel easy to digest for the masses, but still complex and exciting enough for the diehard fans," said Kreisberg. "We're trying to do the same thing this year with Earth-2 and the concept of the multiverse, and the concept of doppelgängers. We've been having a lot of fun with that and getting glimpses of Earth-2 probably sooner than people would've thought. It's still 'Flash.' It's still the same show. It still has those characters and that camaraderie, but our villains are coming from a brand new place, and we're dealing with different concepts, and it's just really exciting."

What's also exciting? The new powers Barry will pick up for his season two adventures -- and one of them will be unlike anything comic fans have seen before. "We're going to be seeing him learn a couple of new tricks. One from the comic and one that we actually have come up with, and that we're actually really excited about. The thing about the Flash that's fun is there's always something new to figure out for him to do with his powers, so that it's not just him running in and running around really fast. It's one of the endless gifts of the show."

"The Flash" returns to the CW tonight.