The Bodendieks' pension is not enough for them. So the couple decide to rent it out. What they hadn't planned, however, was that they let out the good room twice - he to the young Lisa, she to Klaus, who is almost the same age. As business-minded as the Bodendieks have become, they believe they have double the income when they realize that Klaus works nights. But things only get tricky when Klaus is in bed during the day and Lisa's boss comes to visit...