Re-reading Chamber of Secrets, though, I realized that if you know the whole story in advance (Spoiler alert: If you don't know the whole story, you probably don't want to read this), Snape does something extremely brilliant and very sad in the book. He manipulates Harry into a position to see if Harry might become the vessel for the return of Voldemort.
It happens in the scene where Snape “assists” Lockheart in teaching the children how to duel. Snape maneuvers Harry and Draco so that they’ll fight each other, and right before they start, he whispers something in Draco’s ear. As soon as the boys begin, Draco busts out a spell that sends a snake at Harry.
Question is, why would he do that? We know from earlier in the scene and from later books that Snape himself is a duelist of great caliber, inventing his own spells to use against enemies. He could have dropped any number of hints to Draco, and yet he picks the one that summons a snake.
The reason is that he wanted to put Harry into a position to see just how much of Voldermort was inside him by testing him in an emotional situation to see if he was a Parselmouth. Keep in mind that even though we the audience don’t know anything about the horcruxes that maintain Voldemort’s undead form at this point, Snape is almost certainly one of the few people who do know about them. Once it became clear that Voldemort’s soul had possessed and even mutated Quirrell in the first book, Dumbledore and Snape would immediately have begun researching how he had managed to do so if they hadn’t already known. It’s clear from the fact that Dumbledore had already injured himself at the start of Half-Blood Prince by putting on the ring horcrux, and Snape’s conversation in flashback about the foolishness of doing so, that they had both already begun researching the concept prior to the book. Harry’s task to retrieve memories from Slughorn was simply to confirm it and, hopefully, find out how many Voldemort created since they knew there must have been more than one.
So when Chamber of Secrets begins, Snape knows it’s at least possible that a portion of Voldemort’s soul is inside Harry. He almost certainly would have heard about the zoo incident from the first book involving a snake, and by the time the duel scene happens, there have already been attacks by the basilisk from the Chamber of Secrets, with Harry being near one of the attacks and having a personal connection to the victim of another. Parselmouth was a rare gift in wizards, and a very good indicator that Voldemort might be influencing Harry.
Consider what this means for Snape, knowing what we now all know about him and Harry’s mother. Being tasked with protecting Harry is one thing, but possibly having to watch the boy turn into a new version of the man who killed the only love of his life? Failing that badly? It must have been an unspeakable fear to overcome.
The way the duel scene is described in the book, Snape is incredibly relieved when the serpent moves toward Harry and Harry does nothing to defend himself. He even tells Harry in a kindly way not to bother doing anything because he’ll take care of it for him. Whatever else Snape doesn’t like about Harry, Snape has this moment of peace knowing that at least Harry won’t become the host of Lily’s murderer.
Then Lockheart screws it up by blowing the snake into the air and pissing it royally off so that it goes to attack another student. Suddenly, Harry orders the snake to stop, and it obeys without question. In the midst of all the sudden gasp from the class over Harry's being a Parselmouth, Rowling remarks that Snape gives Harry “a cold and calculating look he didn’t like” before the scene devolves into the students' remarking on their distrust of Harry.
Snape gives Harry that look because he’s wondering if he is going to have to kill him to prevent Harry from becoming the next Quirrell or worse. He’s wondering if some sort of transformation has already started and is causing his students to be attacked. He’s wondering if instead of looking into Lily’s eyes when he stares at Harry across his classroom, he’ll see Voldemort’s.
Of course, none of that came to pass, though it does make Snape’s death at the fangs of Voldemort’s snake in the last book somewhat ironic or at least oddly poetic. Still, it’s interesting thanks to hindsight to read Chamber of Secrets and know that the secret hero of the series is fighting an inner battle that no one realizes, and that he used Draco and the pretense of a dueling club to gain intelligence in that fight. As Harry said to the son he partially named after Snape, “He was the bravest man I ever knew.”
Jef's collection of short stories about vampires and drive-thru churches, The Rook Circle, is out now. You can also find him on Patreon, Facebook and Twitter.