After a couple of decidedly filler-esque episodes, To Aru Kagaku no Railgun's fifteenth instalment finally returns us to the world of the proper story arc, in a story which begins with Kongou Mitsuko surrounded by a bunch of unruly-looking delinquents. Such trifles should be of little concern to a level four esper, but when Kongou suddenly finds her head hurting and her powers not working, it's left to a mysterious man to step in and save her from being attacked.
It turns out that the gang in question are part of "Skillout", a bunch of thugs with no esper powers who have therefore chosen to hang around in large groups and use their numerical advantages as a way to pick on those who do hold esper powers. More specifically, it appears that Kongou's assailants are part of a sub-group of Skillout known as "Big Spider" - A name which seems to bring back some major jolts of past memories for Judgment's Konori.
With attacks from Big Spider on the increase, it is of course up to Judgment to do something about it, but with Konori supposedly busy it's left to Kuroko and Mikoto to visit the makeshift "headquarters" of Big Spider to see what they can do about bringing in the group's ringleader, a man who calls himself Kurozuma Wataru; another name that clearly rings a bell with Konori.
As their investigation progresses, Kuroko and Misaka find themselves saved not once but twice (once needlessly, but the second time when they find themsevles in dire straits) but a mysterious milk drinking man; the same man who saved Kongou earlier. Just who is this guy with the spider tattoo on his back? Why, he's also Kurozuma Wataru - The real one this time.
Although this isn't shaping up to be To Aru Kagaku no Railgun's finest story arc from the looks of this particular episode, it's a pretty solid offering that at least promises to give the otherwise neglected Konori some time to establish herself, while it also gave us at least a little of the action quotient which has been so lacking from the past two episodes, with Kurozuma's "return" proving to be a stylishly brutal affair which was probably worth the price of admission alone. Maybe I'm just getting a bit soft in my old age too, but for once I actually found myself laughing at Kuroko's antics with regard to Mikoto, whereas that whole scenario is normally one I simply find tiring. Anyhow, hopefully any revelations about Konori's past in the next episode can serve to make this story arc more interesting still, but I have my suspicions that it might all end up being rather predictable...