There is a clean smell, like grass or mint that has been walked on. There isn’t any hissing smoke like some sci-fi movie, only a set of doors with fold-out stairs underneath them. When they open, they are silent. The ones inside creep forward, they are like grey cats and army troops with night vision goggles. They come down the stairs, composure and control perfect, ready to pounce. Inside the ship the scent is a clean metallic tang, a bit like human blood. The young ones are silent, except for their breathing. They wait nervously, forming little huddles purely for the feeling of security. Suddenly they know.
They walk out slowly and cautiously, but they lack their guardian’s easy grace. They move as swiftly as they can without making noise. As they come to the tunnels, the adults head back. When the ship lifts off, there are no special lights or streams of smoke, or even a whisper of sound. All that is left is the scent of crushed grass and maybe a hint of mint too.