Later that night, they break into the library. Sam zips up the stairs to retrieve the book while everyone else waits for him in the lobby. Sam quickly finds where Rabbi Bass switched the bird book with the ledger. An instant later, a dart zips through the air and hits Sam just under his jaw. A bruise fans out from the puncture. Sam stumbles. "I owe you thanks," the Nazi firebug says. He appears from behind a shelf, blowgun still in hand. "The rabbi led me this far, but you took me all the way." Sam kicks a filing cart at him and stumbles back down to the lobby. "Necromancer!" he gasps for an explanation. He falls, unconscious, onto the landing. Aaron gets darted in this belly and falls. The golem is just standing there, not looking too worried. It takes Dean sending him after the Nazi to set him in motion.
The Nazi darts the golem to no avail. The golem smashes him into the shelves hard enough to buckle the metal. He drags the Nazi down the stairs and deposits him before Dean. "Long live the Thule," says the Nazi, right before the golem twists his head like a bottle cap. At once, Sam's bruise begins to fade.
Later, young Bass wakes up in the back of the Impala, surprised to find himself alive. "The Men of Letters healed you," says the golem, standing watch outside the car. A short distance away, Sam and Dean dig a grave and deposit the dead Nazi into it. While they work, they wonder about a backup plan to off the golem. "Unless you think Aaron could get a handle on him," Sam says. This is the first time anybody's said the kid's name, which is dumb. In all that exposition, you'd think he could have found time to introduce himself. "My crazy rabbi grandpa was a member of the Judah Initiative, which fought the Thule Society, which funded the Nazi party, and also my name is Aaron and I am not actually hot for Dean Winchester as far as you know." Aaron watches in horror as the brothers douse the body with gasoline and set it ablaze. "Oh, my God. These guys are psychopaths." To illustrate the point, Sam takes the opportunity to warm his hands over the roaring fire. Hee.
The next morning, everybody regroups at Aaron's house for some more sitting around and reading of stuff. Sam has typed some of the ledger into an online translator and confirms that it's from Belarus. Aaron realizes that it's the red ledger that was supposedly destroyed and that his grandfather has been searching for. "It describes the horrible experiments performed on the camp's population -- magical experiments," Sam says. "More horrible than words," says the golem. He was made to destroy that place, he says. Sam tries to get the golem to explain what he means when he tells Aaron to take control. The golem just cranky about how Aaron should already know. It turns out that Rabbi Bass gave his grandson a sort of golem "user's manual," but Aaron used the pages to roll joints when he was in high school. Everyone gives him varying degrees of disappointed looks. "Why can't you just tell me what I don't know!" he shouts at his golem. "It's not my place!" the golem shouts back. He stomps off in a huff.