Wir könnten, wir sollten, wir hätten doch...

Sunday night in snowy Germany. On television, the usual news about refugee disasters on the coast of Italy, in the kitchen Sushi is being stacked on a plate. A couple tries to spend a cozy evening, but suddenly a stranger, who is freezing outside, is ringing the doorbell. This sparks a quarrel about what they could do, should do, or have to do...