How believable is the creature?
I think they did an excellent job of making a believable creature. The best part is that it is reminiscent of the Creature from the Black Lagoon with the fins from the elbows. So there is a bit of charm there in that the movie is set in the 1960s during Jim Crow era.
In the original Black Lagoon, the creature is hunting an expedition member by member and even kidnapping the female Kay to his lair. Eventually the team finds the monster, riddles his body in bullets and he sinks to his death.
This movie has similar origin, but without mentioning it is the Gillman creature. This time they actually have captured the creature and are medically examining/torturing the creature. Here the story has an added Soviet espionage element that is part of the Soviet vs US competition in science.
The lead expediter of the original science trip that captured the creature is very dispicable: he has no compassion for the creature and regularly beating the creature. As they cannot uncover that the creature is unintelligent and need to dissect the creature to gain anything of use. The secret Soviet spy scientist actually does realize that the creature is intelligent and is trying to figure out how to rescue the creature. His Soviet handlers have other ideas in mind to keep the US from gaining any knowledge either.
Instead of being the victim of the story, she is actually the unexpected hero. She has been born as deaf mute, which is the ability to hear, but no vocal cords. So she passes through the world almost unseen, but she becomes the only one able to communicate to the creature. They grow closer over time until she realizes that they will execute the creature soon. So she takes drastic measures to save the creature and hide him in her house until he is safe to escape into the harbor and likely swim back to the Amazon.
Are there interesting technical aspects to the film?
Yes, I believe the whole film is filtered in bluish-green to green depending on the seen, which could be seen as symbolic of the creature's habitat and the creature. Seeing as the film is set in the 1960s, you almost don't notice the filtered film scenes due to the great character development and background sets and costumes.
Did you have any art related to an unexpected heroine?
I do, but of a different era, time, religion, continent and age. This girl Malala was simply attending her father's school for girls in Northern Pakistan, when she was targeted as an agent of the West. She got involved with the blog to discuss her living under the Pakistani Taliban, sponsored directly by the Pakistani government despite being a US ally. She was shot in the head by the Taliban and then taken to London fro treatment. She continues to speak out for girls right to education in Pakistan to this day.