Colton Haynes' Roy Harper has role in changes in Arrow season 4 premiere(Photo : Astrid Stawiarz | Getty Images Entertainment)

It is an open secret that "Arrow" season 4 premiere will introduce the "real" Emerald Archer of Star City.

Cast and executive producers of the CW Network TV series confirmed in earlier interviews that Stephen Amell's Oliver Queen will no longer be the Arrow that he is in the first three seasons.

He will now be called the Green Arrow, his original nickname in the DC comics where the show's characters were based from.

What prompted the show to embrace such change in the upcoming "Arrow" season 4 premiere episode? Executive producer Marc Guggenheim it is the event in third season involving Roy Harper (Colton Haynes).

"That's definitely the thesis statement of episode 401, the season premiere," Guggenheim told Green Arrow TV when asked about the major shift in fourth season of "Arrow."

"He can't be the Arrow anymore, because everyone believes that Roy Harper was the Arrow, and Roy Harper is dead, at least as far as everyone believes. So, he had to adopt a new identity. All of this is explained in the season premiere; we come straight out with it."

During the San Diego Comic-Con last month, Stephen Amell confirmed he will be wearing a green suit with lighter shade in "Arrow" season 4 premiere.

Aside from new identity, other things Oliver Queen will have to deal with in the pilot episode is his issues with other members of Team Arrow. The biggest is the hate Diggle (David Ramsey) feels towards him because of what he did to Lyla.

"Dig has a huge bone to pick with Oliver when they see each other again, at the top of Season 4," executive producer Wendy Mericle said in an interview with Collider.

"We're gonna work that out. It's not gonna be easy. With what happened to Dig's family, it's really tough to buy that back, and Oliver is not gonna to be able to. Obviously, they can't be mad at each other forever, or what are we doing? But also, in the intervening months while Oliver has been gone, Dig has, more or less, been leading the team. It's a little bit more democratic, Speedy and Black Canary are both super bad-ass and kicking butt. He's not happy, when he and Oliver meet again. It's not an open-armed, "Hey, buddy, all is forgiven," reunion."

"Arrow" season 4 premiere is on Oct. 7.