Ep 23. Lian Yu

Oliver faces his biggest challenge yet in the season 5 finale of Arrow, titled "Lian Yu." As Prometheus sets his final plan in motion and takes Oliver's loved ones hostage, the Green Arrow must team up with old allies and enemies alike to try and stop the madman before it's too late.

The episode begins with a flashback to the island of Lian Yu, where Oliver Queen (Stephen Amell) has spent so much of his time since becoming Green Arrow. In the present day, we see a group of mercenaries arrive on the island with an unconscious Oliver in tow. As they set up operations, we see that Prometheus (Josh Segarra) is behind it all, and that he has Oliver's loved ones - Felicity (Emily Bett Rickards), Thea (Willa Holland), Curtis (Echo Kellum), Rene (Rick Gonzalez), and Quentin (Paul Blackthorne) - being held captive.

Prometheus's plan is revealed - he wants to make Oliver suffer by making him watch as his loved ones die one by one. Using the gadgets and traps he's set up all over the island, Prometheus sets about hunting down each of the hostages, forcing Oliver and his allies to scramble to save them. Along the way, they enlist the help of Slade Wilson (Manu Bennett), who has been locked up in a secret ARGUS facility on the island.

The tension slowly builds throughout the episode as the stakes continue to rise. Every time it seems like our heroes have gained the upper hand, Prometheus unveils another twist that puts them back on the defensive. There are plenty of action-packed sequences, with Oliver and his allies taking on Prometheus's minions in a variety of creative ways.

As the episode nears its climax, we finally get to see Prometheus and Oliver face off in a brutal showdown. The two men trade blows and insults, with Prometheus seeming to have the upper hand until Oliver manages to turn the tables. In the end, though, it's clear that Prometheus has one last trick up his sleeve - one that threatens to destroy everything Oliver holds dear.

The final moments of "Lian Yu" are tense and emotional, with some major developments that will have huge implications for the show going forward. It's a satisfying end to what has been a strong season for Arrow, with plenty of great character moments, tense action, and surprising twists along the way.

Overall, "Lian Yu" is an exciting and satisfying finale for Arrow's fifth season. While there are some minor issues with pacing and plot contrivances, the episode does a great job of bringing together the various plot threads of the season and delivering on some major emotional beats. Fans of the show and the character should be pleased with how this season ends, and eager to see where Arrow goes from here.