Under the sea, humans are vulnerable. They swim slowly, can hardly see, hear nothing and can’t breathe. Against a fifty-foot monster, they are even weaker. On this aspect, the movie succeeds in establishing the stress factor. Nonetheless, luck takes part in the draw and our CIA agent can take more. It is why he also concentrates on a fight to the death with the manipulating terrorist. The terrorist doesn’t like the CIA agent, the CIA agent doesn’t like the crew, the crew doesn’t like the octopus and the octopus doesn’t like anyone. All these elements give birth to an entertaining yet irrational film with both its positive and negative aspects.
While the terrorism aspect succeeds much more than the horror aspect, Octopus isn’t an action movie. The budget probably couldn’t afford to show us the 3D octopus very often and this was the alternative solution. The octopus is horrendously badly animated and superimposed. The scenes are frequently cut and we don’t really witness what is going on. Furthermore, the monster seems to have eyes on the end of its tentacles because it succeeds in searching the vessel and capturing its passengers by "running" after them. This is very frequent for invader films that were shown in drive-in theaters in the fifties and sixties: this seems to be the desired effect.
The army and the police are brought in to face the danger and this is the reason why one or more heroes of the sort leave the spectator indifferent. Here, we try to show the more human side of a geologist and of the CIA agent however the attempt fails. However, the fact that the geologist is attractive, smiling and rarely dressed doesn’t harm the film at all.
The last twenty minutes bring in a new incredible coincidence that close the two events that started the film (terrorist and octopus) in one blow. Because I do not wish to ruin the surprise, lets just say it is satisfactory yet predictable, just like the movie is in general.