A review of tonight's "Louie" coming up just as soon as I fart for science...

"In the Woods" puts the various arcs of season 4 on hold for an epic-length (without commercials, the "episode" runs 66-plus minutes) flashback to Louie's adolescence, as catching Lily smoking pot reminds him of one of the dumbest episodes of his life.

Louis C.K. grew up in the era of the "After School Special," well-meaning but often unintentionally hilarious stories trying to warn kids away from drugs, drinking and all the other tomfoolery teenagers get up to. (Here's an excerpt from "Stoned," produced the year before "In the Woods" is set, starring Scott Baio as a straight-laced student whose life falls apart after he experiments with the marijuana.) And though C.K. has much greater command of tone — and respect for his audience's intelligence — than the makers of those specials did, there's always a danger with this kind of subject matter that it could trend too much towards melodrama.

But even though dramatic things happen in the span of "In the Woods" — Louie curses out his father, his mother screams that she doesn't like him anymore, a friend gets arrested and a drug dealer gets physical with Louie — it's ultimately a small story, where the stakes are more about Louie getting into emotional danger rather than the physical or legal kind, and is more powerful as a result. Whether or not the story is autobiographical, it feels like something that could have happened to the real Louis C.K. at that age, and it also feels like something that is a part of the show, in the same way "Louie" has managed to do episodes about suicide, Afghanistan and replacing David Letterman and have them all be "Louie."

We open our trip back to 1981 showing Louie as a bright, mostly happy kid who gets along well with his mom and has a great rapport with his wonderful science teacher Mr. Hoffman (played, tremendously, by "Third Watch" alum Skipp Sudduth). He gets bullied by Danny (in one of the episode's lighter moments, Danny schedule's Louie's future beating like he's a doctor arranging a follow-up visit) and is no better at talking to women than he will be as an adult, but he's doing okay.

Then he and his best friend and Danny smoke one joint together, and his life takes a turn — not in a way that destroys his future forever, but simply in a way that lets him know how weak he can be and how much he can hurt people who believe in him like his mother and Mr. Hoffman.

Amy Landecker returns as Louie's mom, having last appeared late in season 1's "God" after previously playing Louie's date in "Bully," and "In the Woods" really goes to town with the double-dipped casting. F. Murray Abraham returns not as Uncle Ex (nor as the creepy husband who wanted to watch Louie have sex with his wife), but as Louie's father, while the social worker Louie visits is played by Josh Hamilton, who was Louie's stoner neighbor Jeff back in season 1's "Dogpound."

After that first season, C.K. said he used Landecker in those two different roles simply because he liked her, not because he was trying to make any kind of commentary about Louie being attracted to a woman like his mother. Abraham, meanwhile, returned as Uncle Ex mainly because C.K. felt the Oscar winner didn't have a role worthy of his talents the first time around. But whether or not Abraham and Hamilton are here specifically to evoke the last roles they played on the show, "In the Woods" does that, anyway. Louie's dad doesn't seem quite as cultured as Uncle Ex, but there's a certain old-world haughtiness to both men that explains why Louie would be so uncomfortable around one because he reminds him of the other. And while Louie here has a very strong memory of his time smoking pot and the misery he and others experienced as a result, in "Dogpound," he tells Hamilton's character simply that, "I guess I just grew up, stopped." Still, both this episode and "Dogpound" suggest that C.K. takes a view of heavy marijuana use not unlike the one espoused in the classic "Freaks and Geeks" episode "Chokin' and Tokin'": pot's not going to kill you, but it's going to waste much too much of your time that could be better spent doing almost anything else. If Louie's friend Brad is even 30 seconds later, Louie's perhaps deep in conversation with Mr. Hoffman's daughter Danielle, he never goes into the woods, never befriends Danny, never finds out that Jeff Davis(*) needs new scales, etc.

(*) Played by Jeremy Renner, who co-starred with C.K. in "American Hustle," even though I don't recall them sharing any scenes together. It's a nice character turn for Renner, whom I think has been miscast as an action movie hero, but can slide into a genial dirtbag like Jeff with ease.  

Yet the fact that Mr. Hoffman is named after Philip Seymour Hoffman, whom the episode is dedicated to (because he was apparently supposed to appear in it), and who died from his own problems with drugs, casts the episode in an even darker light. Young Louie gets out of his bad period — though who's to say what path he might have been on had he not arrived in high school carrying the scars and reputation from the previous year? — but as adult Louie hugs Lily, the look on his face seems equal parts sadness for the end of his daughter's childhood and fear for what other kind of trouble she might get into as she grows up. But his approach with her once the initial anger subsides — recognizing that the only words that will have value to Lily in this situation are "I love you and I'm here" — suggests that, if nothing else, that stupid time when he was 13 at least helped him become a better parent, even if he understands that he may one day feel about Lily the way that his mom felt about him during this period.

Did this story need to be 66 minutes, plus ads? I imagine some of the beats could have been tightened up, but the loose atmosphere, and all the '70s/'80s soundalike rock on the score helped convey what Louie was (and wasn't) feeling during this hazy, stupid period of his life. I'm more curious to see next week's closing chapters of both "Pamela" and season 4 as a whole, to get a sense of why C.K. decided now was the time to interrupt the present-day arc for so long, rather than concluding the season with the incredibly moving "In the Woods."

What did everybody else think?

Alan Sepinwall may be reached at sepinwall@hitfix.com