For me, any episode with Barbas, played by Billy Drago, is probably going to be a good episode. Barbas is a unique figure in the Charmed pantheon. He is a demon, but he doesn't operate in the normal demonic fashion. Billy Drago plays him with the self-assurance of any top level demon, but also with a creepy amusement. Here is a demon who truly enjoys his work. Barbas here is the blueprint for demons to follow in later seasons. He is a normal-looking human dressed in all black. He even calls himself a demon. We have everything here except the fireballs.
It is Friday the 13th, and this episode continues the horror elements from last episode. The foreboding manner in which this episode was shot adds to the effectiveness of Barbas's rather famous first appearance. I especially love how Barbas waves his hand and a shadow passes across the face of his victims. Very creepy and very cool!
This is mostly a Prue-centered episode. Prue overcomes a couple hangovers from the death of her mother and ultimately vanquishes Barbas, until next time, rather anticlimactically. Probably a bigger result is that the sisters are drawn closer together as a result of the trial. This episode also clearly established Prue as the strongest sister, the sister of action; that would be highlighted for the next couple episodes.
Phoebe's subplot is a further revealing of her good witch nature, which I'm sure we are all aware of by now. She is momentarily the righteous one, until Paige shows up, when her character takes a pragmatic turn. Alyssa looks fantastic here, BTW.
Piper's subplot is irritating frankly, but I am always irritated by any subplot involving Piper and any man but Leo. At least it is always fun to watch Piper.