unfeasible (adjective)

1. In the novel, the characters attempted to travel faster than light, but it was an unfeasible task due to the limitations of physics.

2. The protagonist's plan to save the entire kingdom single-handedly was seen as unfeasible by the other characters.

3. The film portrayed a utopian society where everyone lived in harmony, but such a perfect world is unfeasible in reality.

4. In the cartoon series, the characters attempted to build a time machine out of household items, but it was unfeasible and never worked.