So there is the physical:
Or there is a metaphor… Okay, I’m stuck. Its the balloon. All I see is, well, a balloon.
“Whose idea was it to use balloons?” The man next to him shrugged. They had watched one go up three hours ago. It had been green, meaning all was okay. Then an hour and a half later an orange one had been released. Now it was red. A small girl came up and looked across the city with eyes that had seen too much. “They gone?” she asked and then put her thumb in her mouth.
“Don’t worry Suzie,” the guy said. “We will be fine.”
The story is about survival. Basically, the city is overrun with ghouls. Ghouls are like zombies but they only eat the un-animated dead. So they kill you and then eat you. Each building is filled with trapped people. They have devised a way of communicating using balloons.
A red balloon floats over London in cheerful grace unconcerned about the screams that surround it. Suzie is ten and she watches it rise with dread knowing that the ghouls have taken another community.