I love Supernatural. For me, it's the best Sci-Fi/Fantasy series currently in production, and I've been watching it since Episode 1. They bridge the plot lines between seasons so well, infuse new characters without ever truly "jumping the shark", and the humor is just awesome.
To compare to other series out there:
I tend to think of the first three seasons at least as kind of a "freelance x-files", and even some episodes after. Just instead of using UFO's as a long term story ark, there are a few other main antagonists. (Note: no significant UFO content in this series, if that's what you're looking for.)
I'm Not much of a Buffy the Vampire Slayer fan, but I know a lot of people who liked that and like this. On the other hand, I find Supernatural to be a lot grittier, better special effects, and less comic-book like than any of the episodes of Buffy I've seen. So don't take one for granted as the other.
For those that are looking more for a "scare the crap out of me, can't go to bed" type series, I have to say it's a 50/50 shot. On one hand my girlfriend will not watch this without me there and spending the night, so for some it will have that effect. On the other hand it's been rare that I've had trouble sleeping.

Sorry for anyone who's looking for comments on this season in particular, I like the series enough I'm currently in the habit of just buying them all so I can re-watch in future years... except I will comment that Castiel became of my favorite sci-fi characters ever. :-P

Supernatural is one of the most interesting and underappreciated series on TV. It combines humor, horror and spiritual themes without being saccharin. Although Christianity is not at all overt in the series, the mindset and stories come from the last several millennia of Christian thinking. Siupernatural makes a statement that dabbling in witchcraft and demonology is dangerous and wrong. The rituals are strongly based on John Dee's enochian work, including the sigil of Amareth. Incredibly well done. I don't understand how they hooked up with a technical advisor that was so well versed. My only complaint is that a coujple of demons are named "Aleister" and "Crowley," which I think is rather uncalled for. Many of the bad guys are named after goetic spirits, which is quite appropriate. As a member of the OTO, I love the use of the unicursal hexagram as the sigil of the "Men of Letters," identified later in the series. This season is the beginning of the time when the series really hit its stride.

Oh, boy. I love this show, and I had trouble respecting this episode.

It's a disjointed, quickly-thrown-together, crappy episode. It hurts to say that about one of my favorite shows, but there you go.

Negatives:
1) the Ruby character--oy. Where to begin. Will she ever really be more than a prop? I don't know. But she isn't more than a prop in this episode. She feeds Sam some lines that help shape later bits in the episode, but otherwise, she does a lot of screaming and bleeding and not much else.
2) Castiel and Uriel--they are wasted here (although Castiel actually is a plus in some ways--see below). They come for Anna, ostensibly to kill her, and they of course encounter resistance from the menfolk, who just don't get that these angels aren't all warm and cuddly and. . .well, angelic. No, they have a mission, and sometimes the stuff they gotta do is horrible. Why is this surprising to the Winchester men? I dunno. Anyway, these two angels get short shrift here, and it's annoying that Castiel, in particular, gets used that way. Also--what's up with the whole Alastair-can't-be-killed thing? Does that mean he's better than an angel of the Lord, or what? Utter confusion. So--these guys get used in the plot line, and all that happens as a result is that the viewer gets utterly confused. Perfect.
3) The whole plot line is convoluted and filled with happenings that don't make much sense. Pamela comes back to help Anna figure out what's really in her head that she can't remember, but that comes from left field. And almost everything that happens here seems disconnected. Maybe it's that so much is left kind of unexplained, and the show won't be on again until January, so eh? I'm confused, unsatisfied, and basically left to be so for another two months. Fantastic.

Good stuff:
1) Jensen Ackles. He's been kicking acting butt for two years or more now, and he just gets better and better. This guy knows how to make Dean vulnerable, and his willingness to just put Dean Winchester out there and let him be human and flawed and in deep, deep pain, with all the acting challenges that comes with--well, kudos to you, Jensen Ackles. You are superb. From the way your face can show childlike glee (think the "Mystery Spot" episode) to the way your eyes can actually go blurry and your face seem to crumple in on itself from guilt and self-loathing. Oh, yeah. The last scene in this episode is a perfect example of what I mean. Every muscle twitch, the way you refuse to stop those tears--a long time coming, they are--to just overflow, and the way every single emotion is just. . .THERE. Awesome. Someone give this man an Emmy.
2) Castiel--like Jensen Ackles, Misha. . .what's his last name? Huh. Can't remember. Anyway, the guy who plays Castiel. He can convey so much with just a subtle shift in expression. At one point, when Anna realizes that Dean has given her up to Uriel and Castiel in order to save Sam from death or a quick toss into the pit of Hell, she turns to Dean and tells him she understands and forgives him. The camera pans to Castiel a couple of times, and the longing in his eyes (for the human emotions that angels aren't supposed to feel or enjoy having) as well as the respect he has for Dean and the decisions he makes at risk of his own sanity and happiness--all there on this guy's face and in his eyes. Good job here, too.

Those are the only two positives I can see in this episode, but they were enough to keep me from giving it one or two stars.

Hopefully the new episodes in January will return with the quality of the first four or so of this season.

Again--someone give Mr. Ackles an Emmy or a People's Choice or something. Wow.

This is a show that only gets better with time. Every season the writers find new and creative ways to keep us coming back. We all knew that Dean would not stay in hell forever, and I was very curious how he would get out. Never did I imagine that in addition to all the demons and ghosts we would have angels too.
This season the main story line revolves around the book of revelations in the bible. The demons are breaking the 66 seals nessasary to raise Lucifer from hell, and the angels are supposedly trying to stop it. It turns out that while Dean was in hell, he broke the first seal and put everything in motion.
Dean, Sam and Bobby are working their hardest, along side the angel Castiel, to prevent the seals from breaking, but are not haveing much luck. It turns out that some of the angels want lucifer to rise in order to force a battle that they are convinced that they can win.
The entire season is not completly dedicated to the angels and demons storylines. It would not be Supernatural if it did not include a few episodes mixed in that make us laugh. My 2 favorites are Wishfull Thinking, and Yellow Fever. Wishfull Thinking involves residents of a town whose every wish is being granted via a wishing well in a chinese resturant. The only problem is that the wishes go bad. Dean test it out, and wishes for a sandwich, only to get food poisoning from it, and a little girl wishes for her teddy bear to become real and life size, only to get life size teddy that drinks all day, steals porn, and tries to commit suicide because he feels that life has no meaning. Yellow fever involves a new twist on the tradional ghost story. Dean and Sam head to a town where healthy residents are droping dead of heart attacks. It turns out that they are infected with ghost sickness, which makes them afraid of everything, extremely paranoid, and will die after 3 days unless they scare the ghost into exercising itself. Dean winds up infected and there is an extemely entertaining moment of him running down the street in fear of his life from a small dog with a pink bow in its hair.
The season finale does a grerat job of wrapping up the season and setting up the next season. We also find out the full truth about Ruby, and she gets what has been long coming to her. The only real sour note is the ongoing storyline of Sam being addicted to demon blood. I thought that was a little to crazy even for this show.
The dvd extras are a little thin, but I recommend that everyone pick up this season.

Though most on this forum have given the show kudos for the angels versus demons storyline, I have to give the writers their "props" for finally bringing Dean, wonderfully played by Jensen Ackles, to the forefront of the season. The character gets to mature, realizing his place in the ongoing battle against the forces of evil as well as being Sam's (Jared Padalecki) protector, even when the younger brother is toying with his own inner "demon". Ackles shines in "I Know What You Did Last Summer", "The Rapture", the season opener "Are You There, God? It's Me, Dean Winchester", and the season-ending "Lucifer Rising". Why he nor Padalecki have not received Emmy nominations is a further indictment against the decision makers of The Academy of Television Arts and Sciences.

Fine acting is also provided by Jim Beaver as the dependable and Johnny-on-the-spot Bobby Singer, Misha Collins as Castiel the angel, Genevieve Cortese as the "is-she-a-good-demon-or-a-bad-demon" Ruby, Robert Wisdom as Uriel, and Julie McNiven as Anna. The casting of "The X-Files" Mitch Pileggi as the Winchester boys' grandfather in "In the Beginning", as is the father-son team of John and Michael Rubenstein, along with character greats Barry Bostwick and Richard Libertini in "Criss Angel is a Douche Bag," another outstanding episode.

"After School Special" features younger versions of Sam and Dean, played convincingly by Colin Ford and Brock Kelly, respectively. The installment also makes a commentary on the cruelty of high school students against each other.

"Monster Movie" brilliantly pays homage to the classic horror films of the 30's and 40's, complete with period music, costuming, and black and white filming.

As a whole, the season features excellent writing, top-knotch direction, scoring, and some true thrills. Because of the intensity of the latter, the writers separate the chills with some comedic and satirical dialog, many delivered by sardonic bliss by Ackles.

The compilation features audio commentary on two episodes, deleted scenes, and a "gag" reel that's not very funny, just a chance to see the guys mug for the camera.

Castiel!!!!!! 1 of the most favorite characters to ever be created in Supernatural history and glad they kept him as a regular. The start of the Angelic wars and the end of the Sam/Dean wolf pack. I hate to say it but I was glad sam and dean was not the dynamic duo anymore but the awesome 3 Sam, Dean, and yes Castiel. Glad they started the heaven wars or at least a supernatural version of what angels should look like. I cant be the only guy that thinks every angle was perfect or was this sweet boy that only acted good, did good things, or was royal in every aspect of life. Cant wait to re watch Castiel's rise to Fame and the Winchesters intro to God, heaven, My lord etc.

I am a prophet of the lord. hear me Sand and dean winchester. heehhehe

The familial chemistry of the Winchester brothers is back and harder than ever to beat for entertainment in this season. This go round, each actor continues to bring a wide range of human emotion to his role and is man to the task as the brothers take separate paths.

The conflict between brothers, demons and angels escalates this season. Episode 1 begins with Dean crawling out of a grave, no longer a captive in hell, but uninformed as to why. He quickly tracks down Sam and the two are off again, fighting, laughing, making choices, and interacting more intensely than ever before. The "Supernatural" mythology introduced in previous seasons continues to develop and, by the end of the season, it's clear that this show could easily go another two seasons (and I hope it does).

The "Monster Movie" and "It's a Terrible Life" episodes are excellent.

(Probably the most bothersome thing about "Supernatural"--and it's not that big of a deal--is when Dean and Sam are working on a ghost case, discover the remains have been cremated and then say something to the effect of, "There must be a lock of hair around or something." I mean, anyone who's ever been alive must have left hair, fingernail clippings and microbes all over the place. . . . Minor gripe.)

And after four seasons, I still don't know who my favorite show-brother is, which (for me) is a strong indication of how well-written and well-acted this TV show really is.

The saga of the Winchester brothers continue in Season 4 and the series just keeps getting better with each passing year. The forces bent on turning Sam and Dean into enemies are hard at work and it is this tension (will they succeed?) that keeps the viewer watching episode to episode. This season the boys get visited by Angels; the question is: are they truly here to do good? Also included is a great episode that is shot in black and white and which harkens back to the good ole days of the old Universal horror movies; it's a real treat. We also discover that there is a third Winchester son. As with the previous seasons, there are plenty of monsters, ghouls, and creatures of the night to keep the Winchester boys busy...but it is their changing relationship that is the real point of interest.

This season comes in plastic inner packaging with the DVDs separated onto plastic holders, so the packaging isn't quite as sturdy as previous volumes. Still included, however, is the program guide and some great special features which explore the history of Heaven and Purgatory. For any SUPERNATURAL fan, this season is a must-have. After watching all the episodes don't be surprised if you want to watch them all over again immediately. It's that good!