In picking what article to go out with before our Comic Con induced hiatus, there was one thing that was nagging me for so long it just could no longer be ignored. Pouring through all the clips and pictures of my vast collection, I set out to uncover the mystery. I'm talking about the enigma known as Sam Winchester's hair. 
Just like Sam, his hair has been wandering from place to place, never finding a real purpose in this world. We have to wonder if Dean's consistent clean cut look and Sam's ever changing mess is a reflection of the paths their characters have taken. Nah, I'm reading way too much into that. Still, hair doesn't lie. Let's go through the seasons and see if there's any plausibility to that theory.
Season One
Pilot Hair
Not half bad. Sits nice, has a bit of wave, and definitely makes him look like the younger brother.  A good way to kick off the series. It makes the statement, "I'm Sam, an ordinary guy, but I have a good idea of who I am." Boy, does that change.

Wendigo Hair
Sam loses control fast.  His lack of care could be blamed of grief, but all that's needed here is common sense. By cutting the top shorter, the bangs are meant to hang down evenly now. Too bad they don't! Plus, the top looks matted half the time, kind of like hat hair, and the sides look like they’re fighting each other, taking any direction they want. Sadly, this look sticks for a while.

Home Hair
This is the "Sam needs to fire his stylist" hair. The jagged layers flop on top in a disorganized clutter, there's some sort of curly action going on in the back that's hardly flattering and most of the episode it looks like he just got out of bed. Granted, both Jared Padalecki and Eric Kripke said in interviews for most of season one they had no idea who Sam really was. I guess they found the hair to match that. It still makes him look like a pup though.

Provenance Hair
Skipping forward a bit, Sam has indeed fired his stylist by this time because it doesn't look like the hair has been cut all season. There's one side effect to growing out the top layers like that. When he combs his hair (like on his date with Sarah), he looks like one of The Beatles, circa 1964. While the look works for comedic pleasure with Howard Wolowitz on The Big Bang Theory, here, um, no.

Devil's Trap Hair
Yikes! He's totally given up. I get that Sam's face looks like he went a few rounds with a two by four, which he kind of did, but does the hair have to suffer too? Parts are flat and matted, one side flies away like he stuck his finger in a light socket and there's no sign of even a vague attempt at style. Just get to a barber and at least do something about the split ends. Heck, use Dean's machete. Anything!

Next page, Season Two, aka, the vast improvement.

Season Two
The best hair season ever. Not too many hot messes here, and it's continued growth throughout the season got better and better. Heck, it even looked good when he was praying to the porcelain God in "Playthings."
Bloodlust Hair
I'm not sure why, but this episode is sort of a turning point. Sam goes from that pup look to a real man. The hair is well feathered on both sides, has a little personality, a little style, and makes him oh so sexy. Even when bound and gagged after having a bag over his head it wasn't bad. 

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Born Under A Bad Sign Hair
Even manic, tied to a chair Meg!Sam looked pretty hot with those dangling bangs covering the face. Forget all the other times with the evil leer and perfect coif. Fine packaging indeed.

Heart Hair
This episode put Sam's hair through the ringer, and it passed with flying colors. It's the indestructible hair style! Case in point, an entire day of passionate love making. Sound asleep, naked in each others arms, and his hair is perfect. That episode is all sorts of win. 

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All Hell Breaks Loose Hair
Well, if you're gonna die in your brother's arms, you might as well go out looking fabulous. What a pretty corpse, and even when waking it looks pretty well done. It just goes to show you, always keep your hair in check, just in case you get stabbed to death. 

Next, season three and it's tragic toll...

Season Three
We go from best to worst. The only explanation I have is budget cuts. They couldn't afford to give the boy a haircut.  Sam's hair wasn't cut all season and by the finale, there was no hope, kind of like Dean's fate. I get that Dean was dying and all but sheesh!
Bad Day At Black Rock Hair
Okay, your bangs and top layers are getting a little too long. You a) trim them up a bit so they lay right or b) let them flip up in a haphazard flyaway style that makes you look sort of girly. Okay, not sort of. Good luck or not, the rabbit's foot didn't do Sam's hair any favors. 

Red Sky At Morning Hair
I bring this one up only because of one thing, Winchesters in tuxes. So, did the hair match the hotness of the monkey suit? It most certainly did. See what happens with a little attention and some hair gel?

Mystery Spot Hair
Does this even need a comment?

Long Distance Call Hair
This is the mother of all bad hair days. There's profound evidence he did use Dean's machete this time. 
The layers from earlier in the season have grown out, so why not try to feather what's there behind the ears? Er, doesn't work. What results is a flat looking disorganized jumble that looks like he hasn't washed it in a month. The way the hair parts at top of the head is a disaster and the exposed forehead is so blaring we need sunglasses. Judging by how much better it looked in next episode, "Time Is On My Side," I'm thinking he got a hair intervention.   

Next, Season Four...

Season Four
A definite improvement, just like the whole season. For most of the season it remained manageable, with a few noted exceptions. It seems that exercising demons with your mind doesn't require good hair. Sam has to be grateful for that.
Lazarus Rising
A bit of trouble here, but at least he worked in a cut during his grief. It's far better than when he wept over his brother's demise. I hope the new look made him feel better. Hair has to be shorter though when pulling demons with your mind, but that also must generate electricity given how his hair flipping up in retreat, just like Dilbert's tie. He ended up working out that side effect later though, you know, when he got better and stronger. 

I Know What You Did Last Summer
Sam's emotional state might be all over the map on this one, but for some bizarre reason, his hair looks great in every scene. Kinda hot actually. Maybe the hair symbolizes, "Barely holding it together?" Nah, I didn't think so either. It even manages to look so fine when he's drunkenly killing another crossroads demon and not so successfully fending off advances from a horny one. However, winner in this episode is when he stitches his own wound before tending to Dean's dislocated shoulder. I'd be tearing my hair out over that much pain. Sam decided otherwise and damn was that a wise decision.

On The Head Of A Pin
If you're going to torture and kill a high level demon with your mind, might as well carry the style that fits. Granted it doesn't look as great at it could, but at least it's out of his face so we get the full effect of all those twisted facial expressions that are required in zapping a baddie to oblivion. 

When The Levee Breaks
The rare time where a mess is a good mess. This is Sam at his lowest point, and the hair tells the sorry tale just as effectively as the haunting makeup. Heck, even in that state it looks way better than all of season three. And season one. By this time, Sam's identity and his hair are clearly one in one. 

Hmm, I guess there is no pattern. Sam's hair stubbornly does what it wants, and its caretaker isn't in the mood to fight it. He's got bigger fish to fry. We don't mind either, for we love him bad hair or not.  So, what's your favorite Sam hair episode? Your least favorite?