In the scene portraying the nadir of Heidegger's career, he is standing far upstage, on the backdrop of a screen properly illuminated for a Nazi parade, wearing a Nazi uniform (the lighting, very impressive in general, was done by Keren Granke). Oded Kotler, with a haircut reminiscent of the Fuhrer's, looks like the real thing throughout the play. And here – and mainly in the explanations by Heidegger and Arendt for his behavior, in hindsight, the metaphor of the hammer and the carpenter, the tool and its user, resonates. The music heard in the background is Mahler's Sixth Symphony, chosen, no doubt, because the composer was Jewish, although Wagner would certainly have been more suitable and right for the spirit of the period and of the man.
Heidegger believed he was using Hitler, while pretending to be an obedient tool, to resurrect the genuine Germany. Arendt claimed the Nazis used him. On the other hand, Arendt understood during their relationship, certainly even more toward the end of her life, that she was a willing tool in Heidegger's hands, and he used her. The fact that he enjoyed it is not relevant here; she enjoyed herself, too.
In short: The philosopher and his student can philosophize about themselves, about the carpenter and about the hammer. But they, and all of us, merely function as a hammer. We are convinced that we are hitting nails on the head, or are iconoclasts, but in the final analysis the driving hand – our passions, history and simple human irony – use us.