The action-packed Season 4 premiere of "Arrow" began with a slow start but ended with a major cliffhanger that has left fans desperate for more.

At the beginning of the episode, Oliver and Felicity were seen living a peaceful life in suburbia, away from all the madness and crime in Starling City. However, it wasn't long before Felicity became bored and started to miss the thrills of fighting crime in the newly renamed Star City. It was also discovered that she was working with Team Arrow behind Oliver's back, reports Forbes.

Eventually, Thea and Laurel summoned the lovebirds to return to Star City to help them fight against the "Ghosts." The new big bad, Damien Darhk, was also introduced as he plotted to destroy the city.

However, the finale scene in the premiere left fans biting their nails after a flash forward suggested that a significant member of Team Arrow will die six months into the future. In the clip, Oliver and Barry, aka The Flash, are standing over a fresh grave. There are also hints that Felicity was the person that was buried, notes USA Today.

"We don't necessarily know who it is right now," said executive producer Wendy Mericle at a press screening in reference to the mysterious dead person, reports TVLine. "We're still figuring the plan out for the season, but we want it, obviously, to have resonance. If it doesn't mean something to the characters, it won't mean anything to the audience either."

A new trailer video teases that the next episode, "The Candidate," will be just as thrilling as the premiere. In the episode, "Star Trek: Voyager" alum Jeri Ryan is seen as Jessica Danforth, a family friend of Oliver and Thea who wants to run for major, despite the dangerous risk.

Echo Kellum will also be introduced as Curtis Holt, and eventually transition into the superhero known as Mr. Terrific.

According to ComicBook.com, the synopsis reads as follows:

"When an old family friend, Jessica Danforth (guest star Jeri Ryan), tells Oliver (Stephen Amell) and Thea (Willa Holland) that she is going to run for mayor, both Queens are concerned considering the last three mayors have been murdered. Despite their protests, Jessica makes her announcement so the Green Arrow and Speedy vow to protect her. Meanwhile, Thea begins to exhibit effects from the Lazarus Pit. In addition, Felicity (Emily Bett Rickards) is faced with a tough business decision and looks to one of her employees."

"Arrow" Season 4 Episode 2 will air on Oct. 14.

Watch a promo video below.