The girls might have resolved their differences with Rei, but as we reach the finale of Vividred Operation that still leaves the small matter of the Alone's mastermind taking on Rei's power with a view towards obliterating the entire planet.
Such is the power manifested in this "final boss" that it seems as if absolutely nothing can stop it, not even our fully equipped heroines. With this last Alone all set to fuse with the Manifestor Engine's energy and cause a reaction which will blow the planet to smithereens, is there anything left to be done? Yes there is in fact, as it soon becomes clear that Rei is alive and well within the behemoth attacking the planet.
With a renewed determination to save their friend (and maybe the Earth to boot), and in spite of assertions that they have absolutely no chance of victory, the quartet set off to give it all they've got in tackling the Alone, looking to break Rei free of her current prison. Of course, the relationship between Akane and Rei might also just prove to be the key to overall victory and saving the planet...
After a great couple of opening episodes, Vividred Operation's biggest problem was frequently its predictability, and it was this issue which also reduced the effectiveness of its finale, which felt telegraphed from the first moment to the last. Although it never quite descended entirely into "monster of the week" territory, there weren't enough twists and turns to add anything significant to the show's narrative, and its characters were never quite strong enough to pick up that slack. Ultimately then, Vividred Operation could be looked at as "Strike Witches without the charm" - not a bad series by any stretch, but one which stepped away from any number of interesting directions it could have traveled in to leave us with a fun but somewhat vacuous anime.