Schlüsselkinder.

Katleen is 17 years old and lives with her brother Torben in their spacious family house. Her mother is a travel writer and is practically never at home. There is no mention of her father ? he left the family years before. Brother and sister live in a close, symbiotic relationship. They close themselves off from the world around, thinking this gives them total security. They communicate with each other in the form of habitual codes and games involving psychological twists, which always turn them back into their bond.