It seems like Laurel might find out that Oliver is Arrow in season 2 episode 19 of Arrow.

First PHOTO of Harley Quinn on the Set of Arrow Revealed

Oliver's real identity might finally be revealed to some characters -- including Laurel and Detective Lance -- in the next episode of Arrow, which is suggestively titled The Man Under the Hood. 

The Oliver Slade feud will heat up in the next episode as the Deathstroke returns and is waiting for Oliver and his team in their lair. Things will get tense as Slade catches hold of Thea in front of Oliver.

The Joker from the Dark Knight to Appear in Episode 19? 

The first images of DC comic characters Vibe and Killer Frost who will appear in The Flash were also revealed with the preview of the episode.

Here's the official synopsis for The Man Under the Hood:

Thea Kidnapped By Slade, Learns Big Secret About Oliver that Creats A Rift in Episode 18?  

"Deathstroke Hits Oliver at Home - Oliver (Stephen Amell), Canary (Caity Lotz), Diggle (David Ramsey) and Felicity (Emily Bett Rickards) return to the lair and find Slade (Manu Bennett) waiting for them. An epic battle breaks out and one member of Team Arrow is sent to the hospital. Thea (Willa Holland) hits her breaking point, but just as Oliver is about to reach her, Slade intervenes and Oliver is faced with a choice - his battle with Slade or his family. Meanwhile, Laurel (Katie Cassidy) struggles with a new secret. Jesse Warn directed the episode with story by Greg Berlanti & Geoff Johns and teleplay by Andrew Kreisberg & Keto Shimizu."

Episode 19 will air on CW on April 16.

Watch the preview for The Man Under the Hood here: