Last week's episode of "Arrow" finally shed some light on why Damien Darhk had Diggle's brother killed. According to Darhk's file, Andy wasn't just a target; he was competition. When Captain Lance (Paul Blackthorne) told Diggle this news, Diggle didn't want to believe it. This week, in the episode titled "Brotherhood," not only does Diggle (David Ramsey) have to deal with this painful revelation, but he comes face to face with his not-so-dead brother, Andy. This encounter sends Diggle spinning, and the typically calm and collected Diggle has a hard time finding any hope in the situation. Oliver (Stephen Amell), Felicity (Emily Bett Rickards) and Laurel (Katie Cassidy) all try to convince Diggle to rescue his brother from H.I.V.E., but he is too mad to even consider the fact that Andy (Eugene Byrd) might need their help. It is in these scenes that theme of "Brotherhood" really comes to the surface. If Diggle really loves his brother, he should do everything he can to rescue him, right? It's what Oliver did for Thea (Willa Holland), it's what Laurel did for Sara (Caity Lotz) and it's what Diggle should do for Andy. Unfortunately, his pain blinds him, and he can't see past Andy's betrayal to help him. Thankfully, Diggle is a part of a team of people who never take "no" for an answer when someone needs saving.

The quest to recover Andrew Diggle (named after "Green Arrow: Year One" writer Andy Diggle) leads Team Arrow to Darhk's secret base in Star City Bay. The discovery of this base inspires Oliver to start a Star City Bay restoration campaign. This campaign announcement brings Darhk out in the open, and he attempts to bribe Oliver with offers of money and media attention if Oliver leaves the Bay alone. Darhk's request tempts Oliver, and Oliver is left with the tough choice of working with Darhk from the inside of H.I.V.E., or to fight him in the light of day as the future mayor of Star City. Diggle, in addition to being mad at Oliver for wanting to rescue Andy, is furious with Oliver when he finds out he is even considering working with Darhk. Diggle's confrontational and brutally honest speech to Oliver about "fighting in the light" convinces Oliver that he can't work with Darhk and that he must not be afraid to confront him over the Bay project. This confrontation sets Oliver and Damien Darhk (Neal McDonough) at odds, which will definitely spell trouble for Oliver in the future.

Two things to note about Oliver's upcoming war with Darhk: Darhk will claim the life of someone both Barry (Grant Gustin) and Oliver love. Oliver and Barry were both standing over a grave in the season four premiere of "Arrow." Also, Oliver is still carrying the spell that John Constantine (Matt Ryan) gave him on the island. Constantine said that Oliver will need the magic contained within the spell to overcome a force more powerful than him. At first it sounded like Oliver would need the spell to fight Baron Reiter back on Lian Yu, but the tattoo could still be seen on a recent modern day scene with Oliver and Felicity. This tattoo could mean the difference between life and death in an upcoming episode of "Arrow."

Thea discovered something tonight when she's faced with Damien Darhk. When Darhk tried to use his magic on her, to suck life out of her, he was mysteriously unable to. When he touched her, not only could he not harm her, but she actually was harming him. His face began to age and transform, possibly due to the residual effects of the Lazarus Pit. When she told her father, Malcolm Merlyn (John Barrowman), she also shared that him touching her got rid of her blood lust. Merlyn didn't seem to know exactly why this happened, but Darhk's magic will probably be what cures Thea by the end of the season.

In the hunt for Darhk's ghosts (and Andy Diggle), Ray and Felicity are able to discover what chemical substance Darhk is using to wipe the ghosts' DNA markers in their teeth. While working on this project together, Felicity asks Ray why he's not coming back to Palmer Tech. Ray says it's because he wants to be a part of something important, but we all know where he's really going -- The CW's new show "DC's Legends of Tomorrow," although Ray won't figure that out until the upcoming two-night Flash"/"Arrow" crossover event.

Tonight's episode concluded with an epic Team Arrow raid on Darhk's compound. Diggle was able to rescue his brother with the help of the entire team, including Ray Palmer and his awesome A.T.O.M. suit. Back in the Arrowcave, Andy confesses that everything in Darhk's file is true, but it's possible he's still under the effects of Darhk's mind control pills. Diggle will have to wait to get answers out of Andy because the next episode of "Arrow" is the crossover, which will be all about protecting Hawkgirl (Ciara Renee) from Vandal Savage (Casper Crump).

Special mention goes out to the director of this episode, "Arrow" stunt director James Bamford. He's been working in Vancouver stunt work for a long time, and tonight was his episodic directorial debut. The episode featured some amazing long-take fight scenes, including an stunt sequence that began upstairs, continued in an elevator, and the concluded on a lower level. These action-packed one-shots are what makes superhero television so fantastic these days. Congrats, James!