This review is for the whole "In The Woods" story line; I didn't even realize it was actually counted as 2 episodes until seeing it listed on IMDb. I guess I watched a later airing where it appeared all at once, which seemed like the best way to see it, because this was more like a 90 minute movie than any TV show I've ever seen.
As given in the short plot description on the main page for this episode, Louie catches his 12-year-old daughter smoking pot, then he recalls the first time he tried it. The present day sequences are really only a few minutes here; almost the entire time is spent in flashbacks to Louie's childhood in 1981. We get to see an extended story of young Louie's life, and I won't reveal any details of that, but suffice to say that quite a bit happens. The whole time I'm watching the flashback and wondering how this experience is going to affect adult Louie's handling of the situation with his daughter. When we do finally come back to present day at the very end, I was not disappointed.
The story is told so beautifully and with such care, it was amazing. Touching, poignant and funny in parts, this was far more of a drama than a comedy. As any fan of the show knows, Louis C.K. is not afraid to take risks with his show, and it pays off big time here. "In the Woods" was better than 99% of the feature films I've ever seen. Brilliant!