*Spoilers Ahead* Once Oliver Queen retired from being the Arrow in the season three finale to leave town with his new love interest Felicity Smoak it didn't take long for him to return back to action in season four.
While Oliver and Felicity were enjoying their life away from Star City, what was left of Team Arrow were fighting bad guys on their own led by former Arrow partner, Diggle. In the team, Thea as the Red Arrow and called Speedy, The Black Canary, and Diggle dressed as some super hero in a helmet that looks like a cross between Judge Dredd and Magneto, know that they are up against a challenge that is bigger than them.
Damien Darhk is the main antagonist in episode one of season four and appears to be the main villain throughout the season. He reveals to be the leader of an army of militant terrorists called H.I.V.E.
Laurel and Thea both know they need the help of Oliver and Felicity so they recruit them back on the team at the reluctance of Diggle. It is only when Oliver returns that he is fitted with the more traditional sleeveless Green Arrow costume from the comic book and introduces to the city that the former Arrow had died and he is the Green Arrow.
It is at the convincing of Diggle's wife, Lyla, that Diggle begins to be more open to Oliver being back on the team.
In a twisted turn of events it appears that Officer Lance may be involved with H.I.V.E. in some capacity. This is a plot set up for the remainder of the season.
The Arrow Season Four premiere is action packed from the beginning to the end. It is a fun show to watch and still has the flash backs from five years ago. There isn't anything wrong with this episode except the fact you wished you had more.
It was well scripted and wonderfully acted. Arrow season 4 premiere was one of the better premieres of the series.