CW announces 'Arrow,' 'The Flash,' 'Legends of Tomorrow,' 'Supergirl' crossover special

LOS ANGELES, May 19 (UPI) -- The CW announced that its four DC Comics superhero shows will come together for a special crossover episode in December.

CW President Mark Pedowitz alluded to the idea of the universes of Arrow, The Flash, Legends of Tomorrow and the newly acquired Supergirl coming together in a crossover which he called "our biggest ever."

"Just imagine what our superhero crossover episode is going to look like come December," he said.

Entertainment Weekly reported that the crossover episode of the shows, all produced by Greg Berlanti, was later confirmed by Pedowitz during a presentation on Thursday.

"Next season, Arrow, The Flash, Legends of Tomorrow, and now Supergirl will join forces in our annual crossover event, our biggest ever," he said.

It was announced last Thursday that Supergirl will move to the CW from its sister network CBS.

Pedowitz commented on the move, saying that it belonged on the network with Berlanti's other shows and would remain largely similar in tone following the move.

"We are sitting down with Greg Berlanti and his team next week or so," he said. "We have a rough idea where they're heading and, because our working relationship with Greg, we're confident they understand what our needs are. As for the tone or tonality of the series, they did have a pretty successful series. The fact it's now moved to The CW, where it should have been in the first place, I don't think it will have a big impact on the tone."