Over the past four seasons, Arrow has done an impressive job of building up a cast of fascinating supporting characters. Sure, many of them are drawn directly from the pages of the comics - but, it's to the show's credit that they have all been brought to life so convincingly, here. This episode does a particularly good job of show-casing just how important the supporting cast of Arrow has become to the show's success.
Colton Haynes' return as Roy Harper was, of course, treated as the main draw. He is not the only long absent character to suddenly reappear, though - with Nyssa al Ghul (Katrina Law) making an appearance. But, the episode also finds time to work in a surprise cameo appearance for Tatsu Yamashiro (Rila Fukushima), perhaps better known to comic-book fans as 'Katana'. And, also, there is the even more surprising reappearance of Shado (Celina Jade), a character who we saw die during the second season. On top of that, even characters who have not been absent for quite as long are given some renewed attention - with both Malcolm Merlyn (John Barrowman), and Curtis Holt (Echo Kellum) reappearing.
With so much ground to cover, it would be easy to imagine this episode collapsing under its own weight (as some previous, and similarly plot-heavy, episodes of both Arrow and The Flash have, in the past). Somehow, though, the writer's of this episode were able to find a way to juggle each of it's various plot-threads in a way that actually worked - giving each equal focus and development without undermining any of the others.
Roy, meanwhile, found himself forced into a more antagonist role as he entered to episode - being blackmailed by the Calculator to steal the components he needed for the device he intended on building. It was a very interesting way to bring the character back - particular since, even knowing that Colton Haynes would be reappearing, his reveal as the masked thief that had been causing the team so much trouble, early on, still managed to catch me by surprise. Of course, we still don't know what the Calculator's ultimate plan was, or why he was prepared to kill so many people in order to achieve it - but, it is also obvious that we haven't seen the last of him, either. So, there is plenty of time for him to, hopefully, evolve into something a little more interesting than the fairly generic villain he appeared to be, here.
Thea's seasonal arc, concerning her efforts to control the Lazarus Pit induced blood-lust she has been afflicted with, took another dark turn, here, as we learn that her efforts to suppress it are taking a heavy physical toll. Sure, the actual explanation of what is actually happening to her (that, if she doesn't kill, then whatever mystical force it was that restored her would take her own life, instead) doesn't make a lot of sense - but, then, the reasoning behind her compulsion to kill hasn't made much sense, either. The whole thing has felt like little more than some vague hand-waving and mumbling about 'magic'. But, that aside, it did allow for some genuinely dramatic moments for Willa Holland in this episode - as Thea found herself confronted by the idea that her refusal to give in to that supernatural blood-lust might actually cost her her own life.
The last time we saw Nyssa (Katrina Law), she was being dragged off to a cell after announcing her intention to kill Malcolm Merlyn at the first opportunity - and, that feels like quite a while ago, at this point. So, it was definitely a nice surprise to see her again, in this episode - especially with the clear indication that she will have a large role to play now that she is back in the spotlight. The fact that, not only is she still intent on killing Merlyn and taking his place as the head of the League of Assassins, but that there are also those in the League who support her does promise interesting developments for the future. Or, at least, it did at the beginning of the episode.
In the end, I actually found myself feeling a little disappoint that Nyssa's ultimate plan amounted to little more than dangling a potential cure for Thea in front of Oliver, in the hope that she might be able to convince him to kill Merlyn on her behalf. It feels like familiar ground, for one thing - with Oliver's refusal to allow Merlyn to be killed being the source of much of his problems with the League of Assassins last season. Also, I just can't help but feel as though it detracts from Nyssa's character, and her status as the daughter of the previous Ra's al Ghul, to turn to Oliver for help, rather fighting her own battles. But, I suppose it's forgivable, provided that it leads to interesting developments in the future. Nyssa's plot-line throughout the episode did take things in an interesting direction, though, when a trip to Japan set her up against Tatsu - with the two engaging in a short, but very entertaining, duel before coming to an off-screen agreement. I do have to admit that, when she first appeared, I was a bit worried that Tatsu was about the become another victim of the upcoming release of Suicide Squad (much like Amanda Waller, and the show's own version of the squad) - but, fortunately, it seems as though that didn't actually happen.
Shado, meanwhile, made her reappearance in this episode's flash-back plot-line, seemingly as part of a hallucination which, at first, seemed depressingly similar to the absurd plot-line Felicity was caught up in in the previous episode. Things did take a slightly more interesting turn, though, with the reveal that her reappearance in Oliver's dream might be tied to whatever magic there is hidden on the island. The vague nonsense we were given about Oliver needing to fight the 'darkness inside of him' wasn't all that interesting, to me - though, the fact that his dream meeting with Shado compelled him to finally confess to the role he played in the death of Taiana's brother should make things more interesting, in the future.
Overall, this was a pretty great episode of Arrow - one with only a couple of small mis-steps, as it managed to juggle an impressive selection of wildly varied plot-lines. More importantly, though, while I still think that Nyssa's ultimate decision to turn to Oliver seemed a bit out of character for her (and, the whole issue of whether or not Oliver should kill Malcolm Merlyn has been explored, in detail, before), that final moment does still seem to set the scene for a suitably tense confrontation, next week.