Well I suppose the first thing we should discuss is that contrary to what the DVD box-art may have you believing, Back to the Sea is in fact a 2D animated film (unlike the CG film it clearly emulates, Finding Nemo).
And if you're wondering how this film can be reviewed prior to its official Region 1 release, do keep in mind that it enjoyed a brief North American run in theaters on account of its origins as a Canadian & Chinese collaboration.
So the big questions then become simple- how is it and who is it for? The answers however, aren't quite as cut and dry.
The plot, or plots as the case may be, show signs of competence here and there but some of the technical limitations of being a bit overly ambitious keep it from ever achieving the type of classic status of Disney/ Pixar film but we'll get to that. For starters the core of this one mimics (almost too closely for comfort) Finding Nemo.
We have a young fish named Kevin who gets netted out of the harbor and deposited into a business-owned aquarium. Once here he encounters a bizarre tank-culture who are unaware that they are essentially imprisoned and tells them it's time to plan an escape back to the harbor. Or "Back to the Sea" as the case may be.
However, there's some added pressure here as poor Kevin didn't end up in an aquarium in a dentist's office but rather that in a very popular sushi joint in New York City. When the residents of this tank get scooped out, they don't return if you catch my drift.
Now where the film varies from Finding Nemo is what's going on in the sub-plots and the trouble with Back to the Sea is that there may actually be a few too many going on for its own good. Among them we have a cook-off going on between the son of the owner of said Chinese restaurant and the son of a rival chef, we have the villain in the form of the guy who scooped up Kevin: a career criminal in fact with a plan to recover a priceless pearl that also got scooped up and deposited into the tank in order to pay off the mob. We have cops chasing criminals, fish plotting an escape, some disturbing (albeit off-screen) suggestion to how living fish become a dish, rebellious sons trying to prove themselves to their dads and so on.
If by now you're thinking this sounds like an awful lot of unrelated material, rest assured it is! In fact, when trying to compress so many story threads into a 96-minute runtime, certain parts become muddled and that's exactly what happens here. Rather than weave the separate story elements together into one cohesive tale, Back to the Sea flops between plots with the randomness of someone flipping through the channels with a remote control. The pacing is pretty sloppy, with climactic moments popping in at inopportune times or even feeling random at spots.
However, to insinuate that the film is a total disaster isn't fair either. It does have some charms- among these is a pretty stellar vocal cast who deliver an honest-to-goodness performance. Christian Slater delivers as the villain, Mark Hamill as the mentally-touched octopus living in the sushi tank, Tom "Sponge-Bob" Kenny, Tim Curry, Tara Strong; the list is long and the performance solid.
Additionally the visuals are quite tight. No they aren't going to raise many brows in this society accustomed huge budgeted computer-generated majesty, but the mixture of cel-shaded CGI and digitally assisted 2D line art really work well in this application.
All in all, Back to the Sea is an admirable attempt at big-budget entertainment that's greatest crime, aside from perhaps ripping off Finding Nemo, is that it's too ambitious for its own good.