"Yes sir! Mr.—?"

"The—I'm Neville Longbottom—the Crabbenwalter's Regenerating Hawthorn produces better fruit if it's hit with a Withering Hex at the start of flowering season. But that only makes sense if it's March so that's probably not it sorry."

"My goodness. Blossom thinning, you know I never would've thought of that? That's a very smart idea. I'll tell you why. Whenever you're sizing up a situation, what's really gonna help you is the specifics—the time of year, the species of plant, and all the little tidbits about how the world works. You see those specifics, Mr. Longbottom. Details matter. I'm not a gardener; you clearly know your stuff; in a real life situation I might've gone on thinking my grandmother had actually hurt that tree, unless I had someone like you, or someone like Professor Sprout, to explain it to me. Yes, a very smart idea. It also goes to show you that the Dark Arts are about use. Now don't get me wrong! There are some spells out there that a person should never use! But see, a Withering Hex is not just for hurting people; it can make your hawthorn tree stronger. And Exigent Exsanguination can be used to kill, but I've seen it save a life of a poisoning victim. Even Dark creatures are very dangerous, we've got to respect them and keep our distance, but they aren't evil. It was springtime, and your grandmother was helping the tree to bloom."

"Alright. Flexible thinking. Question your assumptions. Juggle your theories. Look for other ideas. Use specifics. Are we getting a feel for it now? Any other suggestions?"

Seamus Finnegan raises his hand, introduces himself, and says, a bit stubbornly, "You could just be wrong about what your gran wouldn't do. People are wrong about each other sometimes."

"Oh, yes. Mr. Finnegan is raising a very good point, no doubt about it. People are complicated. They'll surprise you with what they can do, both good and bad. Even your sweet little grandmother—heh, of course I don't mean your grandmother in particular, just speaking very generally— maybe she's not so sweet after all, or maybe someone put her up to it, maybe she's having a bad day. It could be a lot of things. And sometimes you can even reason out why. The point is, we shouldn't let our assumptions and our loyalties keep our minds closed. I don't mean be paranoid! Me, in my line of work, people ask if it makes me paranoid. I like my job. Oh, I like it a lot. And I’m not wound up by it. And I don’t think the world is full of criminals, and full of murderers. Because it isn’t. It’s full of nice people just like you. And if it wasn’t for my job, I wouldn’t be getting to meet you like this. What I'm saying is, Defense Against the Dark Arts often comes down to, not who's the strongest spellcaster, or who got the best grades in school, or the rarest ingredients. Often it comes down to these fundamental skills: can you challenge your basic assumptions? Can you access what you know instinctively? Have you practiced how to respond, over and over? And can you think critically, and can you use your imagination? All of you here today have powerful imaginations, there's no doubt about that either. We're going to learn how to use that imagination, that critical thinking, to find out what motivated your grandmother to hex that tree. We're going to develop these practices, which will make you better at magic, and better able to protect yourself and the people around you from harm."

Whatever else he may be, this professor seems like he intends to teach something, so that's good. Hopefully he doesn't assign too much homework about it.

In no time at all, it seems, Columbo is wrapping up the first Defense lecture of the schoolyear. It's great working with these kids, a real smart bunch.

"... and the nephew had charmed his pest-control box to be a Portkey, so when the boggart climbed in— poof, there went the murder weapon! So the reason we couldn't find a gentleman matching that description, the reason the desk didn't have any axe marks in it, is because he was completely made up! Nothing more than a frightening rumor for the specific purpose of shaping a boggart when she was home alone. Just goes to show you, if you're banging your head against the wall trying to figure out how, you can always try falling back to why— to motive. And, maybe don't put your nephew in charge of pest control, I suppose. Alright, that's the end of the story for today. You all are dismissed; I'll see you next time."

Over the resulting din of shuffling chairs and bags, Columbo suddenly shouts, "Oh wait, I forgot. Uh, just one more thing before you go, it'll only take a moment. For next class, please complete the table of jinxes and hexes from the blackboard. Think creatively— remember illusion magic. You can work together, that's fine, put your heads together, but make sure I can tell which parts were yours. Sign your name by them if you have to. Alright, that's really it. Goodbye!"

Huh, a group project. Hermione still thinks of that as a muggle school thing. It's been a while since she's had to choose between Following The Instructions (doing part of it and letting other people do part of it) and Getting The Right Answer (doing it all herself).But then she realizes that she can just do the whole assignment herself, then help/harangue the other students into doing their parts, and then turn in both copies.

"Welcome, Lieutenant," says Professor Trelawney ethereally. "What brings you to my distant abode? Ah, no, you needn't tell me—you're looking for a book. I have several reference volumes you'd be welcome to borrow."

"Thank you, ma'am, that's very kind of you, I'll keep that in mind. No, this is just an old habit of mine. I like to take a look around, get to know everyone, hopefully learn the ropes, since I'm new here and all. Hadn't gotten a chance to chat at the staff table, they told me you're often up here. Have you eaten?" Columbo hoists a rumpled paper bag. "Made a few sandwiches, plenty to share. That is, if you aren't very busy right now."

"Not at all, my schedule is quite light. Even among witches and wizards, only a few truly have the Gift of seeing what is hidden. I would be happy to dine with you."

"Oh, terrific. Gee, the gift of seeing. You know Hogwarts food is very impressive? I must've tried five or six things already I never had before in my life! What an experience. But sometimes it's nice to have a sandwich. A simple sandwich. Oh, here you go, yeah, take whichever you want. So I was checking out the Hogwarts kitchens. Boy, I tell you, those house elves run a tight ship. Very gracious, incredibly efficient, eager to please. I've never seen spellwork like that before either. Did you know they can apparate anywhere in the castle? And here I am marching up and down these stairs all day, yeesh. To tell you the truth, I think I upset them a bit when I said I wanted to make my own sandwiches. Seemed to take that as an insult. I didn't mean anything by it, that's just what I'm used to. I like to do it myself. So, when you say gift, what kind of gift are we talking about? Astrology or something?"

Professor Trelawney needs to do more exercise to get food than anyone in the castle except Professor Sinistra, and the latter is far less inhibited about ordering room service. A sandwich starts disappearing with ruthless efficiency. 

"Astrology is one of the many methods by which the future may be divined by those with the talent to do so. I am also experienced with palmistry, tea-leaf reading, tarot, and the art of making and using crystal balls. But in truth, the future is sufficiently connected to the past that it may, with sufficient skill, be discerned from almost anything. You are from the southwestern portion of the States, are you not? Have you ever met a fire-reader? It is not my preferred process, but experts can attain remarkable results."

"No, uh. I find I'm interested, hearing you talk about it now, and seeing this very beautiful room, but I'm clueless in that department. I don't even know what those colorful things you've got dangling over there are for. You mean to tell me a person can look at a fire and see what's going to happen in the future?"

"A fire, or the night sky, or tea leaves, or at times the inside of her own mind."

"Sounds like a thrilling kind of life, figuring out the future and all, no matter what tools you're using. Maybe a lot of pressure, too. Do you like what you do? I mean, does it get to you?"

Trelawney's giant eyes turn away from Columbo to look at the floor for a moment. "I'm afraid it does, at times. So many futures are not what one hopes . . . even yours. I see your future descending into darkness . . ." She inhales sharply and makes unblinking eye contact again. "Still, better to know."

"You know, I agree with you? I'd rather know, too, if I could. In my line, I'm always trying to figure out what happened in the past. Same idea, though. Really it's the same thing. Say, maybe I should stop by from time to time, you could show me how it works. Fortune telling, I mean. Tea leaves, cards, palm-reading, whatever. I find it all very interesting, like I said, and it sounds like you know a lot about it. I'd bring along some more sandwiches, or maybe teacakes. Wish I had brought some with me today, come to think of it. We could have tea. Do you have tea? I didn't bring anything to drink."

"I am always happy to teach, though if you lack the gift of Sight I may not be able to do as much for you as you would hope. But company and sandwiches are always welcome, and I can always put on a pot of tea."

Not long thereafter, Harry Potter has detention for grand theft auto. It's not totally clear why it's Professor Columbo's job to proctor this detention, but it isn't totally clear who else ought to do it, given that the majority of the infraction happened off school grounds before the start of the school year. Anyway, here he is.

"Mr. Potter! How ya doing, son? Come in. Just the guy I wanted to see. Well, I know this is detention, nothing we can do about that, but I've kinda got myself into a mess and I could really use an extra set of hands.

See I was walking down to Hogsmeade this afternoon and found this little fella nosing around in the grass. No idea what he's doing there, no collar or anything, really needs a bath. So my question for you is, you ever wash a dog before?"

A bleary-eyed basset hound is slumped comfortably on the floor like a pile of laundry.

So is it Columbo's dog now? Whatever, at least he's not going in the Forbidden Forest again.

"I've washed cars?"

"Good, same principle. For dogs like this, you just gotta keep the inside of the ears dry and make sure you get into all the little wrinkles. You can use magic, or not, as long as you're gentle. My father, smart man, very kind man, not a drop of magic, he's the one that taught me when I was a kid. So that cauldron has water ready to go, not too hot, and this blow-up pool is for the dog to stand in. All we gotta do is get the dog into it. You willing to cooperate, dog?"

The dog gives a doleful sigh.

"I don't know what I'm gonna do with this guy. First he follows me to Hogsmeade and back even when I tell him go home, dog! Now he won't budge. Alright, so you fill up the pool with some water and I'll lift him in. Motor vehicles, huh? You do a lot of work without magic growing up?"

Harry starts transferring water to the pool and shrugs. "Chores and stuff."