'Arrow' Recap With Spoilers: "Crossing Lines"

"Crossing Lines" starts with a beaten and bloody Oliver holding a bloody shank. There's a sequence of guards falling to the ground but we can't see if it's Oliver doing the stabbing.

Felicity is talking to Agent Watson, still trying to convince her to help track down Diaz. Watson tells Felicity to go home and leave the crime fighting to the professionals. Felicity gives Watson a final piece of her mind before stepping out.

Oliver and Stanley are going through the cafeteria line when Brick, Samson, and Turner walk in. Oliver confronts Brick about holding up his end of the bargain and Brick caves and agrees to arrange a meeting between Oliver and a known associate of Ricardo Diaz.

At ARGUS, Diggle is putting his son through a mock interrogation over an empty box of cookies. Lyla walks in and introduces Jon Jr. the to babysitter. Diggle and Lyla are about to leave town on business.

Watson is going over the Diaz case file with a colleague at the FBI. The colleague, who appears to be a surperior, says that she needs to focus her energy on other cases implying he might be in Diaz's pocket.

Felicity and Rene are discussing their options and it's revealed they bugged Watson's office. They try hatching out a plan to sneak into the CDC to try and get further information of Diaz's whereabouts.

In Zurich, Diggle, Lyla, and Curtis are working on staking out Peter Tietjen, manager of a local bank they think has ties to criminal bosses. Diggle and Lyla pretend to be opening up a deposit box storing a valuable painting to give Curtis time to hack into the bank's computer systems.

Felicity and Rene go to speak with Dinah and Agent Watson. Felicity reveals she has a plan on how to sneak into the CDC — and she reveals that Diaz might be after vials containing various strains of diseases such as ebola. She thinks he might release them in the air.

Watson agrees to Felicity's plan and agrees to give her support.

At Supermax, the cell doors are unlocked, giving Oliver and Stanley time to escape to the prison roof and meet with the Diaz associate. They enter the cell they were instructed but they're cornered by Turner and a few of his men.

Tuner tells Oliver that it was all a setup and that Brick had zero intention of helping Oliver out. Brick ordered Turner to kill Oliver. Oliver and Stanley are able to stop Turner and his men and they tie him up.

Watson takes Felicity, Rene, and Dinah to the CDC and the entire group poses at FBI agents to get access to the facility.

Curtis rushes into the safehouse to tell Diggle that somebody copied the data they hacked from the Swiss bank. The two realize that Lyla is the only other person who had access to the data.

The group is staking out a specific room in the CDC and Rene witnesses Diaz and two of the Longbow Hunters enter. Felicity tries to stop them by hacking the doors but she's interrupted by sonic-based frequencies.

Dinah goes downstairs and is soon confronted by Silencer and the two start fighting.

Watson and Rene enter the room with Diaz, Red Dart, and Kodiac and try stopping them. Diaz and the two Longbow Hunters are able to get away. Rene goes downstairs to help Dinah with Silencer, but she's also able to get away.

Diggle tracks Lyla down to confront her about the copied data. Lyla reveals to her husband that she got inside intel of something bigger than what they've both dealed with before and when she ran it up the chain at ARGUS, she kept getting stymied. She's going rogue on this case.

Oliver and Stanley escort Turner to Brick's safe room. Once inside, it's revealed that Brick has been running an in-prison fight club of sorts. There, the group forces Oliver and face off with Samson. In a fight to the death, Oliver ends up killing Samson to make it out of the fight.

He then scales the wall up to Brick's perch with a shiv in tow. Brick explains that The Demon — Diaz's associate Oliver wants to speak with — is located in Level 2, a section of the prison saved the worst of the worst criminals. Upon haring that, Oliver stabs two of the guards helping put on the fight club so that he'll get relocated to Level 2.

After the failed operation at the CDC, Agent Watson reveals that she's been demoted to a desk job. Watson explains that she thinks Felicity did the right thing by going off the books on Diaz.

Elsewhere, Rene reveals to Felicity that he actually captured Silencer and is keeping her at their hideout.

Four members of the prison SWAT team arrive to transfer Oliver to Level 2.