Lagann-hen is an exhilarating production with a setting of monumental proportions, though not without its flaws, which - in some cases - are unfortunately more apparent than in the first installment.
The movie picks up right where Gurren-hen left off, though the opening sequences have been hugely condensed in order to quickly drive the plot into the second arc of the story. The setting expands in Lagann-hen, we travel from Earths surface into interstellar territory, in line with the TV show, although small sections of the story have diverged from the series, some understandably and others disappointingly. Certain new ideas seem extremely rushed, dragging what was a fairly engrossing - if manic - plot downwards. Nevertheless, the scale of the story is as ever admirable and thrilling, though the developmental issues carry over from Gurren-hen, making it clear the Gurren-hen/Lagann-hen film double was more an excuse to cash in on the series, rather than create a coherent piece separate from the TV show. The dialogue, at times, also encountered issues; present simply to move the story along without any natural flow to it.
As in Gurren-hen, the rehashed sequences barely differ - if at all - from the series, but the new scenes go above and beyond. The new ending sequence is a powerhouse of action and zest, which will leave you wishing there was more, but unfortunately, there aren't as many new additions to Lagann-hen as there were in Gurren-hen. The staff really rely on the climatic sequence to blow you away, and while it may do just that, they don't really attempt anything deserving of praise throughout the opening and middle acts.
Taku Iwasaki's score returns for its third outing with no changes, yet the sound and music is a noticeable drop from the first installment. The music felt poorly timed, jumbled and out of place during much of the film, and often it was at such a low volume it may as well have been absent. Even the sound effects, which could have been turned up a couple of notches it give it that extra umph, were disappointing. The sound department manage to redeem themselves a little towards the end with larger emphasis on the music, but it's a shame an aspect presented so well in the series wasn't handled better in Lagann-hen.
Developmental issues mean that Rossiu and Kittan are still very much unknown characters to the audience of the movies, and Lagann-hen does little to remedy this. The film makes use of its supporting cast, more so than in Gurren-hen, but extra screen time doesn't equal development. They are still empty shells with a single trait, which isn't far below their series counterparts, but disappointing nevertheless as they lack any kind of background or character motivation, and the movie absolutely requires you watch the series in order to comprehend the characters' depth.
The stand-out segment in Lagann-hen is the climatic sequence, which delivers and then some, and is probably the sole reason to venture into the second installment beyond just re-watching the series. Pushed for time, Lagann-hen is always moving, but even so it begins to tire. Undoubtedly, far more could have been done to create a more coherent adaptation of the series, and it's unfortunate the studio behind such an enjoyable work would rather cut corners and cash in, than create a comprehensive piece both long-time fans and those new to the franchise can enjoy.