On the latest episode of "Arrow" titled "Keep Your Enemies Closer," Oliver Queen's bodyguard John Diggle (David Ramsey) finally takes center stage. Here are the biggest highlights from the week:

The Wall

We all knew that Cynthia Addai-Robinson had been cast as Waller for this season, but this episode marks the character's first official appearance. Although Waller didn't have all that much screen time, one hugely important piece of information was revealed within the first few minutes of the episode: Waller is fully aware that Oliver Queen is the vigilante and the Diggle is assisting him.

More Than Friends

When Diggle learns his friend Lyla has been captured in Russia, he immediately sets out after her. But why such urgency for a friend and former colleague? Turns out, Dig and Lyla aren't just friends. In fact, they used to be married! After serving together in Afghanistan, Dig and Lyla were married for a brief period of time before Lyla started working for A.R.G.U.S.

Business or Pleasure?

In the comics, Isabel Rochev comes to take over Queen Consolidated as a result of her obsession with Oliver's Dad, Robert Queen. While this has yet to be alluded to or mentioned on the series, Rochev does confirm the fact that she was born and raised in Russia. Also, the fact that her and Oliver hook up in this episode hints that Rochev does, in fact, have a thing for Queen men.

Moira Approves

After an unexpected visit from her mother's lawyer, Thea decides that she has to break up with Roy for the good of Moira's trial. With that, Moira invites Roy to Iron Heights in order to finally meet him. Upon realizing that Roy is what's been pushing Thea forward these past few weeks, Moira gives the young couple her blessing.

Deadshot Still Not Dead

Even though Diggle threatens to murder Floyd Lawton several times, at the end of the episode Lawton reveals that he only killed Dig's brother because he was paid to do so. All this time, Diggle had assumed that Lawton murdering his brother was an accident. Now, however, Diggle knows the name of the corporation who hired Deadshot in the first place: H.I.V.E.

Sarah Lance is a Liar

In a flashback, Oliver is released from his cell by Sarah who claims that she's going to help him escape the prison ship. As Oliver uses a HAM radio to contact Slade and Shado, Doctor Ivo shows up and almost has Oliver killed right then and there. Luckily, Sarah convinces him that Oliver can still be of use to them.

Workplace Romance

As a result of Oliver's hour of passion with Isabel Rochev, Felicity finally expresses her true feelings for her boss. Oliver, who clearly feels bad about the situation, apologizes profusely to Felicity explaining that because of his lifestyle he can't afford to be with anyone who he could actually have feelings for. Felicity replies that he deserves better. Could this be the start of a beautiful relationship? Only time will tell!

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