You'll know in season five.

When Arrow Season 4 premiered last October, a mysterious death was foreshadowed via a flash forward of Oliver Queen standing in front of a grave. Time finally caught up to the protagonists last night in “Eleven-Fifty-Nine,” as Laurel Lance, a.k.a. the Black Canary, was mortally wounded at the hands of Damien Darhk. Before dying, Laurel whispered something to Oliver that fans couldn’t hear, and if you were hoping to learn what that was later this season, bad news: it won’t be revealed until this fall During a press screening of “Eleven-Fifty-Nine” on Monday (via Comicbook.com ),executive producer Marc Guggenheim was asked when the show would reveal what Laurel said to Oliver. This was his vague response:During Team Arrow’s attempt to stop Damien Darhk from escaping prison, Laurel was stabbed by the Season 4 main baddie, who telekinetically controlled some of Green Arrow’s arrows and was exacting revenge for Quentin Lance’s betrayal towards him. Although the doctor at the hospital originally said she would be fine, the leather-clad vigilante soon succumbed to her wounds . Before that, Laurel and Oliver had one, final personal moment together, and during that conversation, she asked him to promise her something. Unfortunately, the camera moved away just as she started talking, and once it was back in the room, that’s when the death that’s been teased for six months finally happened.Some fans wondered if Laurel asked Oliver to help her fake her death (after all, the same thing happened with Roy Harper last season), but Guggenheim ruled that out, so don’t expect any revelations concerning her final words untilSeason 5 unfolds. Right now, the only major development on that front is that Echo Kellum , who plays Curtis Holt, has been added as a series regular, so unless one of the story announcements during the summer hints at something Laurel-related, October is the earliest we’ll find out what she whispered.Despite Laurel’s tragic death , this isn’t the last we’ve seen of actress Katie Cassidy in the DC TV universe. Guggenheim said that Laurel will appear in flashbacks later this season, and her Earth-2 counterpart, who goes by the superhero identity Black Siren , will appear onin a few weeks. As for Team Arrow, Laurel’s death will be a major driving force for them during the remaining five Season 4 episodes as they try to stop Damien Darhk and H.I.V.E. once and for all.returns with new episodes on Wednesday, April 27 at 8 p.m. EST on The CW.