One possible theme could be love. Maybe the 'big red one' is a symbol of love, like a big red heart - shaped object, and the story is about different forms of love such as romantic love, family love or friendship love.
A theme of discovery could also be present. Suppose the 'big red one' is a mysterious object that has been hidden away. The story could be about the characters' journey to discover what the 'big red one' is, what secrets it holds, and how it impacts their lives once they find out.
Survival is likely a theme. How people manage to stay alive in the aftermath of a nuclear war, with scarce resources and a hostile environment.
If such a story existed, one possible theme could be the exploration of identity. The trucker's life on the road and his gay identity could be in conflict or in harmony, showing how he navigates through different aspects of his self.
One possible theme could be family. Indian culture places a great emphasis on family values, so the story might revolve around family relationships, like loyalty, sacrifice, or family disputes.
One possible theme could be discovery. Since it's about a big box, there's likely something to be found inside, like new opportunities or hidden treasures.
One possible theme could be size. Since it's a big pig, the story might explore how being big affects the pig's life, like it might face difficulties in moving around or might be intimidating to others.
One possible theme could be perseverance. The racers keep going no matter how difficult the race gets.
Love and commitment could be a major theme. After all, it's a wedding story.
One possible theme could be perseverance. If the big blocks are obstacles, the characters in the story might need to persevere to get past them.
One possible theme could be danger. Since red can signify danger and 'dark side' implies something negative, danger might be a central theme.
One possible theme could be about transformation. The red soap might be a symbol that transforms the Christmas experience for the characters in the story. For example, it could change someone's view of the holiday.