A man suddenly discovers that he has been possessed, but not by any demon. There's another person now sharing his mind, but the mental squatter is quiet and polite and, in a German accent, asks his host nicely to help him locate his missing body. Together they go on a voyage of discovery: outwardly, to look for the intruder's physical presence, inwardly, to explore the meaning of friendship and the power of empathy. The only similarity attaching these reluctant soul mates together is that they are both university professors in their respective cities, Miami and Regensburg. After transatlantic flights to France, where both had been vacationing, they succeed in finding out how it came to be that one consciousness came to squat inside the other. But the fact that the host is gay and the outsider is not adds a layer of complexity to their relationship, especially when they reveal their secret to their spouses.