In the build up to the debut of the Suicide Squad on "Arrow," the show has released a number of promo videos teasing what to expect in the highly anticipated episode on March 19.

In the upcoming episode, which is aptly titled "Suicide Squad," "Spartacus" star Cynthia Addai-Robinson will guest star as Amanda Waller and assemble an elite team of villains to help defeat a warlord. The team will consist of Floyd "Deadshot" Lawton, Bronze Tiger and Shrapnel. Amanda also asks Diggle to join the team, however, he is apprehensive about leading a group of convicts that could possibly become a bigger threat than the team's actual target. In the meantime, Oliver will seek his Bratva connections for help in tracking down his friend-turned-foe Slade Wilson aka Deathstroke, reports ScreenCrush.

One preview video hints at a flashback to an adventure that Diggle and his ex-wife/current girlfriend Lyla Michaels had in Afghanistan that was alluded to in Season 1. According to USA Today, he is recruited by Lyla for a mission connected to a man he saved years ago in Afghanistan during a special forces operation.

In another clip, Diggle is introduced to the Suicide Squad by Amanda Waller, one of the power players in A.R.G.U.S. He automatically objects to the idea of working with the team of criminals, which includes the man who killed his brother. However, Amanda dismisses his concerns, stressing that she wants a highly skilled group that can just be written off if necessary. Diggle is seen pulling Lyla to the side to chastise her for accepting the mission to work with the villains.

On the other hand, the prisoners seem to have mixed feelings about teaming up with Diggle. Bronze Tiger is pretty stoic about the whole thing, Deadshot treats it like a joke and Shrapnel preps for the mission by reading up on protest literature, notes Zap2It.com.

"Obviously all these characters facilitate the creation and the exploration of the hero. All of the stories lead back to Oliver," said actor David Ramsey. "What's been most impressive is making these other characters interesting but also still connecting them to Oliver without being heavy-handed."

The CW issued a synopsis about "Suicide Squad," which states, "Following Slade's (Manu Bennett) return and his promise to make good on his threat to destroy Oliver's (Stephen Amell) loved ones, Oliver focuses all his energy on preparing for battle with his former friend. Sarah (Caity Lotz) tries to help but, fearing for her safety, Oliver pushes her away."

The synopsis continues, "Meanwhile, Diggle (David Ramsey) is recruited by Amanda Waller (guest star Cynthia Addai-Robinson) and A.R.G.U.S. to stop a warlord (guest star Lee Majdoub) he knew from his time in Afghanistan. Always the solider, Diggle agrees to help. However, he's not prepared when Amanda introduces him to the rest of the team - Deadshot (guest star Michael Rowe), Bronze Tiger (guest star Michael Jai White) and Shrapnel (guest star Sean Maher), all criminals he and Arrow helped put away. Lyla (guest star Audrey Marie Anderson) defends the team and explains the world is a complicated place, but Diggle isn't sure he agrees. When the mission takes a dangerous turn, Diggle is forced to make a difficult decision."

In addition, actor Manu Bennett hinted at what fans can expect to learn about his character Slade's backstory. He opened up to TVLine about Slade's son Joe and how their relationship affected why Slade took Shado's death so hard.

"You have to remember, Slade Wilson has also got an ex-partnership and a son out in the world there somewhere. And the son's potentially got siblings in some scenario that hasn't yet evolved into the storyline," he says. "People have to think about more than the layers of what is being shown in each episode. They have to find clues in the DC Comics history, to maybe even piece together more of what Slade is festering upon."

"Arrow" S2E16, "Suicide Squad," airs Wednesday, March 19 at 8 p.m. EST on CW.

Watch sneak peek clips below.