After an island near Japan has submerged without warning, eccentric
scientist Tadokoro (Keiju Kobayashi) and submarine captain Onodera
(Hiroshi Fujioka) go down in a submarine to see what has happened - and
find some uncomforting developments at the Japanese Deep that will mean
the submersion of Japan in no more than a few months.
Of course at first noone believes the two but an wheelchair bound old
man, Watari (Shogo Shimada) - but he has the means to set up a research
team and have experts figure out some evacuation strategies ... and when
an earthquake hits Japan as a warning of things to come, even prime
minister Yamamoto (Tetsuro Tamba) chooses to listen to Tadokoro's warnings
and take action, trying to evacuate as many as he can of the 110 million
Japanese - which isn't easy, since most other countries have only limited
capacities to house Japanese survivors and are often just unwilling to
accept them into their country ....
Onodera meanwhile plans his own escape to Switzerland with his
girlfriend (Ayumi Ishida), but when she is killed in another earthquake
only hours before their departure, he realizes his responsibilities with
his people and stays aboard, so to speak.
The day Japan effectively sinks, the last Japanese leave the country,
among them the Prime Minister himself. Just before he's taken away by
helicopter, the PM runs across Tadokoro and offers him a lift ... but
Tadokoro is too much of a patriot to leave his country even now ...
By 1973, production company Toho had quite a reputation of
destroying Japan, but up until now, this was primarily done by their
stable of monsters - most prominently Godzilla.
Compared to these rather juvenile monster movies, Submersion of Japan
is much more grown up and dead serious, with most of its destructive
scenarios being firmly rooted in science, which is also explained in the
course of the movie ... which is exactly what is possibly wrong with the
film: Way too much time is spent explaining the science behind the
fictionm as well as depicting the details of the PM's negotiations with
other countries to accept Japanese fugitives, and way too little time is
spent with storytelling and character development, key elements of any
narrative movie. As a result, the film only comes into its own when it
shows scenes of destruction, which are mostly excellent by the way - just
like in these juvenile Godzilla-films.
By the way, in 1975, New
World decided to release the film in the USA with tagged on scenes
involving American (b-list) actors in the proceedings - which makes very
little sense, since the film is specifically about Japan.