Arrow is not quite done with Katie Cassidy.

The former series regular was written out during Arrow Season 4 after Laurel Lance was killed off in a twist that was revealed weeks before her final episode aired.

Cassidy previously signed a series regular deal that spanned The CW's DC superhero universe, but she has only appeared on three episodes as part of that deal so far.

Shockingly, it has now been confirmed the actress will stage a return as Black Siren in the final two episodes of Arrow Season 5, and as a full-blown regular for Arrow Season 6.

Marc Guggenheim had nothing but positive things to say about Katie Cassidy in the casting announcement.

“One of the things that most excites us about Arrow is that we go where the story takes us. Last year, the story took us to the tragic death of Laurel Lance. This year, our midseason finale reintroduced us to Laurel’s doppelgänger, Black Siren."

"We were so taken by Katie’s fearless interpretation of this character that we knew her story was not yet finished."

“We couldn’t be more thrilled to welcome Katie back to Arrow as Black Siren,” he added, “though as her appearances on Arrow and DC’s Legends of Tomorrow this season show, she never really left the family."

Black Siren was a thrilling character throughout her two-episode stint this season, so it should be interesting to see how she is brought back.

Cassidy's next appearance on the franchise will be on the season finale of DC's Legends of Tomorrow, which airs on Tuesday, April 4.

She is slated to appear as Laurel Lance, but other details are scarce at this stage.

Arrow has embraced change this year, with multiple new additions to the cast. The main villain has been somewhat more entertaining than the last few villains.

However, the show has lost steam in the ratings. The current season is averaging 1.8 million viewers and a 0.6 rating, which is down over 30 percent vs. last season.

It has already been renewed, so at least the ratings are not currently a cause for concern.

The series continues this Wednesday with Arrow Season 5 Episode 18, in an hour that will find the characters reacting to Oliver's decision to stop being a hero.

Remember you can watch Arrow online right here on TV Fanatic. Get Caught up now!

Over to you, Arrow fanatics! Are you excited by this casting news?

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