Felicity Smoak (Emily Bett Rickards) will find herself haunted by her past in "Arrow" season 6 episode 4.
The previous episode saw Felicity and Oliver Queen (Stephen Amell) finally making their relationship official and even sealing it with a kiss.
After two seasons of spending time apart, the two finally got to rekindle their relationship in the season 5 finale. But what with the arrival of Oliver's son William (Jack Moore) and the scandal that almost revealed the true identity of Green Arrow, the two didn't exactly have time to talk things out.
But in the season's third episode, Oliver gave Felicity a key to his apartment, signaling a new dawn for the fan-favorite "Olicity" love team. Despite their growing love affair, however, Felicity will choose to face her problems on her own in the next episode, titled "Reversal."
Felicity will have to steal some technology and will refuse her team's back-up despite Oliver's insistence.
"Felicity doing that doesn't always end up in her favor and is also nearsighted... It is one of my favorite episodes ever. I had one of the best times filming that episode," Rickards said in an interview with Entertainment Weekly.
But there's more to the story than Felicity going solo. Black Siren, also known as Laurel Lance (Katie Cassidy), will launch another attack on Star City, just when things are quieting down.
The promo shows her going out on a date with a guy who she eventually kills. Team Arrow is baffled by her latest move. "What do you guys think? Black Siren turned Black Widow?" asks Curtis Holt (Echo Kellum). The episode trailer shows Black Siren stepping up her attack on Star City as she uses her high-frequency scream to break through a facility's security team.
Of course, Green Arrow will get in her way. But she immediately notices something different about him. "You've changed something about yourself. I just can't put my finger on it," she says to new Green Arrow John Diggle (David Ramsey).
Catch the next episode of "Arrow" season 6 on Thursday, Nov. 2, 9 p.m. EDT on The CW.
