'Arrow' season 5 news, spoilers: Oliver Queen becomes interim mayor in fifth installment? New big bad tied to Ollie's past?

If spoilers for "Arrow" season 5 have pinned things correctly, it looks like the upcoming season will be one thrilling ride. Not only is a big bad coming to bring Ollie's nightmares to life but he could also be headed for office at Star City's city hall.

Oliver Queen has amassed his share of enemies, but it looks like one of them will make it his mission to make Oliver's (Stephen Amell) life a living hell in season 5. While Tobias Church (Chad L. Coleman) is still very much a part of the upcoming season, executive producer Wendy Mericle has made it clear that the new big bad will be someone Ollie "unwittingly created" in the first season. Apparently, this menacing villain has spent years training and plotting for revenge and will be "a true dark mirror to Oliver Queen."

Meanwhile, the International Business Times said that Oliver could be giving politics another go this season. It would be recalled that Oliver was forced to quit the mayoralty race in season 4. However, he will be appointed as interim mayor in the upcoming season.

That much is apparent in the premiere episode photos posted on YVR Shoots, with one of the pictures showing him addressing the press at the City Hall. Carly Pope will be joining "Arrow" season 5 as Susan Williams, a Coast City reporter whose focus will be to get a scoop on Oliver.

Amell himself posted a photo on Twitter, alluding to his character's foray into politics.

In related news, Fashion and Style has reported that Oliver would meet a new vigilante, Wild Dog, in season 5's second episode. With the episode's title being "The Recruits," it looks like Oliver will meet Jack Wheeler/Wild Dog (Rick Gonzalez) as he is out fighting criminals and will recruit him to be part of Team Arrow.

Jack Wheeler appeared in the original DC comics as a star athlete and former Marine who became a vigilante determined to clean up the streets after his girlfriend died at the hands of mobsters.

"Arrow" season 5 will premiere on Wednesday, Oct. 5 at 8 p.m. ET on The CW.