To borrow the old and overused Mae West line, when Tom Welling is good, he's good; but when he's bad, he's better.

I hope he gets as big a kick out of playing Evil Clark as I do watching him do so. The way he lasciviously gazes both Lois and Tess up and down as he is either making innuendos or threats, flashing that sly grin in the process, is so precise in its unnerving effect, you don't know whether to swoon or scream. It actually startled me a bit, as it obviously did Tess, when he placed his hands menacingly around her neck as he stood behind her while she tracked Lionel from her desk.

Tom has grown so much as an actor, especially in the last few seasons. His ability to so easily transition from sweet-natured, inspiring hero to ruthless, cold-hearted villain proves to me he'll have a long career after Smallville ends in a few weeks.

I feel similarly about Erica Durance. It occurred to me watching "Kent" just how much I'm going to miss her on my TV screen each week. As this series has progressed, not only has she become more and more radiant, she has also developed into a very fine actress in her own right. Her transition from excited to quizzical to terrified as she realized the true identity of Clark Luthor demonstrated just how far she has come since she first took Smallville frantically by storm. She's more nuanced now, more comfortable in her skin and it shows.

In particular was this true in the last scene between she and Tom on the porch. I admit, I choked up a bit, as I tend to do, when Lois tugged at Clark and said "This Smallville is my home." There was more love reflected between them in that one scene than between Clark and Lana their entire relationship. The chemistry between Tom and Erica has synchronized to perfection in this final season and they have done unprecedented work in portraying exactly why Clark and Lois are destined to be together.

It makes me happy to know that Clark has moved on emotionally and doesn't feel tied to the farm and its memories anymore because it means he is ready to accept his mantle and do what he's destined to do. At the same time though, it feels like  someone is coming into my home, tearing into my photo albums and stealing my memories away one by one.

If the conflicting emotions have been the goal of the writers in this final half of the season, then they have done exactly what they set out to do - and I at once praise them and curse them for it.

It's almost a shame there's another Superman incarnation coming to the big screen, because even though Smallville has been all about the journey leading up to the rise of the Man of Steel, I don't think anything else will ever come close to meeting my expectations like this.

I admit I'm tentative about Tess' loyalties at this point. She seemed to be resistant to Clark Luthor's taunts, and ultimately did throw him off of Lionel's trail, but there was a darkness in her eyes that showed up for a split second, something Emil recognized as well. That is one of the things I love so much about Cassidy Freeman. Her performance has shades of Lena Olin's in Alias as she holds an almost impenetrable poker face. Just when I think I know where she stands, I realize I don't know anything at all.

I've said before I do not want Tess to succumb to the Luthor darkness. I want to see her rise above that and take her place once and for all alongside the heroes, but I'm thoroughly enjoying trying to figure her out in the process.

As much praise as I'm lavishing on the performances tonight, I cannot leave out what, for me, was the standout scene of the night, when the alternate Jonathan Kent, played so breathtakingly by John Schneider, called Clark "son." Just when I think Smallville can't get to me anymore than it already has, they play that card. It brought back all the memories of Jonathan giving advice to Clark while they mended fences and performed other chores on the farm and, of course, the requisite lump in my throat.

Praise and curses, again.

There were only two things that marred an otherwise perfect episode for me, in general:  the grainy, blue tint during the alternate world scenes and the quick attempt at redemption for Clark Luthor. I know the tint was intended to distinguish between the darkness of that world and the lightness of this one, but I found it to be a little distracting. The wrap up with Clark sending Clark Luthor back to the alternate world to be taught by Jor-El just felt a little too swift and tidy for my tastes.

Everything else in "Kent" hit the right spot for me, but nothing can compare to the promos for the finale that aired during the episode. The haunting lilt of the original Superman score cascading over key scenes spanning the ten-year old series gave me chills that traversed my entire nervous system.

In a few short weeks, we'll be leaving behind a series that for many of us has defined our generation. I simultaneously crave and dread that final chapter of Smallville. Despite the highs and lows over the years, there's no other superhero interpretation that will ever come close to holding a candle to this epic series.

Jeffrey Kirkpatrick is a TV Fanatic Staff Writer. Follow him on Twitter.