Katie Cassidy is returning to Arrow as a series regular, reprising her role as Laurel Lance who died in Arrow season 4 - but there's a catch. Cassidy will be playing Black Siren, Laurel Lance's evil Earth-2 counterpart.
Cassidy appeared in the Arrow season 5 midseason finale, and will reprise the role for episodes 22 and 23 of season 5. She'll then be a series regular once again starting in season 6.
"One of the things that most excites us about Arrow is that we go where the story takes us," said Arrow executive producer Marc Gugenheim. "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, though as her appearances on Arrow and DC’s Legends of Tomorrow this season show, she never really left the family."
Arrow season 5 episodes 23 and 24 will air on CW on May 17 and May 24, respectively.