'Arrow' season 4 airs on The CW every Wednesday at 8pm.Facebook/Arrow

Characters and fans of "Arrow" are still reeling from the death of the Black Canary (Katie Cassidy), but the team will have to move forward, and fast, if they want to avenge her death. In the upcoming Season 4 episode 20 of "Arrow," Oliver (Stephen Amell) and Felicity (Emily Bett Rickards) will be seen looking for magical solutions to defeat Damien Darhk (Neal McDonough), as the other members of Team Arrow look at other avenues to stop the impending "Genesis."

As fans know, Diggle (David Ramsey) blames himself for Laurel's death and wants vengeance. He believes trusting his brother Andy (Eugene Byrd) was his first mistake and wants to correct it. In the promo he points a gun at his younger brother, but is soon attacked by Andy's fellow-ghost.

Andy then tells Diggle: "Mr Darhk is on the way... I'm supposed to prep you," as he approaches his tied-up brother with torture equipment. Although Andy has already broken Diggle's trust, we are hoping against hope that there is an ounce of humanity left in him and that he will do the right thing in the end.

Oliver is also looking for a way to avenge Laurel, and with Felicity's approval to "kill the son of a b----," there is no barrier that he won't cross to defeat Darhk. "There is no length that I will not go to, to avenge Laurel... to stop Darhk from hurting anyone ever again," he says in the promo for the upcoming Season 4 episode 20.

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According to the official synopsis for the episode, Thea (Willa Holland) goes on a couple's vacation with Alex (Parker Young), but what should have been a lovely time together turns into a nightmare. Alex still doesn't know that his lovely girlfriend moonlights as the vigilante Speedy and it looks like the cover may get blown in the upcoming "Genesis."

It is understood that fans will finally learn what Genesis is, because the final phase for it is expected to begin in episode 20, or at least Darhk is planning it. However, fans know Oliver and his team will find a way to defeat Darhk before it is too late.

Meanwhile, the hunt for the villains of "Arrow" Season 5 has already begun. According to TV Line, the showrunners have announces the casting call for "James," an "irrepressibly charming man on a mission." He is reportedly looking to avenge a tragic loss he faced two years ago.

The actor can be of any ethnicity, ranging in age from late-20s to 30s, and comes across as a physical threat. He should be able to "just as easily shake your hand as your best friend or break your neck as your worst enemy — and you never know which one is coming. Either way, he's more than capable of having a good time as he does it," reports TV Line.

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