|Enlisted In||German Wehrmacht, Luftwaffe|
|Appearances||Full List of Appearances|
Sergeant Steinfeld, who is one of the camp's guards, appears in three scenes in the episode. At the start of the first scene, he is with several other camp guards, all standing around the truck which contains the barrel that is filled with heavy Water, but which they have all been told is just ordinary water. He confronts Colonel Hogan and Sergeant James Kinchloe when the pair approaches the truck, with Kinch carrying a sign that reads "No Smoking". Hogan tells him that they has been ordered by Colonel Klink to put up the sign. The Sergeant and the other guards become nervous upon hearing this, but Steinfeld protests when Hogan says that the barrel inside the truck is filled with nitroglycerin, saying that it only contains water. Hogan made him and the other guards think otherwise when he reminds them that the truck is being guarded for 24 hours a day. At that point, Sergeant Steinfeld allows Kinch to put up the sign. When Hogan and Kinch leaves, he and the other guards look at each other nervously because they now believe that the barrel inside the truck contains nitroglycerin.
Corporal Peter Newkirk then appears. After he says hello to the guards, he stands in front of the truck and pulls out a cigarette and then a match, planning to smoke in front of them and the truck. Upon seeing this, Sergeant Steinfeld snatches the match while yelling to him, "Nien!" (No in German). He then shows Newkirk the "No Smoking" sign. Newkirk doesn't look at the sign, and after declaring that he is going to smoke, pulls out another match. At that instant, Steinfeld tries to snatch the second match from a soon struggling Newkirk. The Sergeant is soon joined by the other guards, none of them suspecting that Newkirk is actually a decoy, to allow Sergeant Andrew Carter to get into the front of the truck and get a sample of what is actually inside the barrel. After filling up a canteen, Carter exits the truck, while Newkirk is still struggling with the guards. Once Carter is out of the way, Hogan arrives on the scene, demanding that the guards release Newkirk. The guards do so, and Steinfeld quickly informs Hogan that they has been trying to keep Newkirk from smoking around the truck. Hogan mockingly repremand Newkirk for not reading the sign, while pointing it out to him. Upon seeing the sign, Newkirk falsely apologizes for his 'screw-up'. Hogan then falsely praises the sergeant for being on his toes.
Klink then arrives, with a lighted cigarette that is inside a cigarette holder, asking what is going on. Sergeant Steinfeld is about to inform his commanding officer what has just happened, when he sees the cigratte in the holder. The sergeant swiftly knocks the cigratte out of the holder and stomps on it. An angry Klinks demands what is going on, while threatening Steinfeld with a court-martial for his actions. A confused Steinfeld then points to the "No smoking" sign while saying that he is only following his orders. Upon seeing the sign, Klink asks who has put it up. Hogan says he had, claiming that he is only anticipating Klink's order on the matter. Klink is confused by this, before he is soon answering questions by Hogan on what is really inside the barrel. Klink ends the discussion by saying that there is only water inside the barrel. Hogan agrees to accept Klink's word, but he then tells Newkirk, after Klink is gone, that he still didn't believe that the barrel only contains water. Around the same time, Sergeant Steinfield and the other guards are told by Klink to go back to guarding the truck.
He is next seen, still guarding the truck, as Klink appears. After saluting Klink, he is told by him that he has come by to check on the barrel, and that Sergeant Steinfeld is to continue guarding the truck as he does so. He then helps Klink into the back of the truck before going back to his duty of guarding the truck, not knowing that Klink is inside the truck, taking a drink of the water. After a while, he asks if everything is okay. Klink quick informs him that it is, before he exits the truck. He helps Klink out of the truck and is then commended by Klink on his guarding the truck. Klink then tells Steinfeld to continue guarding the truck.
The last time he is seen is during the prisoners' smoke bomb diversion, as he sees the smoke exiting Klink's office and then is the first to yell fire. He is then told by Hogan to move the truck away from Klink's office, unless he wants it to explode if hit by the fire. Still thinking that something volatile is inside the truck, he agrees, but he tells Hogan that he would be the one driving the truck, which Hogan agrees to. Hogan then gives him directions that leads Sergeant Steinfeld to drive the back of the truck against one of the windows of Barracks 2, which is then lowered by Kinchloe and Scotty before they roll a barrel of water into the back of the truck and then remove the barrel containing the heavy water.