"Key & Peele" tweaked its format for its fourth season, whose finale aired last night(*). The main title sequence was replaced by one that spoofed the "True Detective" opening credits, and the live audience stand-up segments were replaced by Key and Peele bantering on an endless road trip through the desert. The driving scenes serve the same function as the ones with the audience — setting up the themes of sketches, and giving viewers a sense of the chameleon-like stars' real personalities — and are likely cheaper and easier to produce. But the two changes felt more than merely cosmetic/logistical. Instead, they seemed like the perfect aesthetic shift to reflect the much heavier comic tone of this season.

(*) Technically, this was only the first half of season 4; the second half wrapped production last month, but won't air until fall of 2015. Comedy Central says they'd like to have more episodes beyond that, but because of the long lead time before they'll need additional seasons, there haven't been any discussions yet.

Like many of the other sketch series in Comedy Central's impressive current roster, "Key & Peele" is filtered through the sensibility of its stars, and initially it stood out for its take on race relations, and for its biracial stars' ability to equally skewer black and white culture. But the series also quickly established itself as visually masterful — whatever style of movie or show is being parodied, you can bet the sketch will look remarkably like the real thing —  and this year added to those two signature elements with an impressive commitment to pushing the premise of sketches in incredibly morbid, unflinching directions.

So we still got Jordan Peele's spot-on Obama impression, like him having completely different interactions with black and white guests at a meet-and-greet, and we got more dead-on pop culture spoofery like the late '80s/early '90s low-budget action junk of "Strike Force Eagle 3." But the sketches that really stuck with me were the ones that went wonderfully, insanely grim.

Case in point: a parole officer insists on one of his charges having a chat with Little Homie:

Or look at this sketch inspired by the aerobics competition video that went viral a while back:

Both of those sketches could have easily coasted on the very first joke of the premise: a parole officer ridiculously trying to use a slang-mangling puppet to relate to an ex-con, and Key and Peele in silly '80s clothing doing silly aerobics moves. Had the show simply done a shot-for-shot remake of the actual Crystal Light video, I don't know that anyone would have complained. Instead, both sketches quickly push past the initial joke and go to disturbing places involving murder and corruption.

Or, for the love of God, please watch this look at strife behind-the-scenes on "Family Matter," with Peele all but unrecognizable as Reginald VelJohnson, and Tyler James Williams doing a terrifyingly good Urkel:

Who does that? Who not only goes to that place, but ends the sketch on that chyron? That is some dark, amazing, balls-out stuff right there.

Obviously, the Halloween episode was going to be filled with creepy material, but would anyone have expected a sketch quite as sick — and with quite as unapologetic a performance from Peele — as this Make-A-Wish bit?

Or look at the punchline to this sketch about a guy shopping for a mattress, whose final punchline puts the entire thing into a tragic new light:

Even something as relatively goofy as "Dicknanigans" — and Internet, where is my 10-minute supercut of Chelsea Peretti just saying "Dicknanigans" over and over? — ends in a very depressing place.

Given the success of the show so far, and the places it's taken both stars' careers, it would have been really easy to come back this season and just coast: do another East/West bowl sketch (even if it's impossible to top the genius of D'Pez Poopsie and Ladennifer Jadaniston), do Obama and Luther as much as possible, and otherwise just keep giving the audience what they want and have grown accustomed to. Instead, the duo and their creative partners decided to try something else, so dark and weird that it could have led to an enormous backlash. Instead, it feels like the fan passion for the show runs even deeper now, as the volume of "OHMIGOD DID YOU SEE THIS SKETCH YOU HAVE TO WATCH IT NOW NOW NOW NOW NOW" emails and tweets I saw this fall seemed exponentially greater than even last year. "Key & Peele" took a big risk, and it led to a huge creative reward.

What does everybody else think? Did you like the new direction this season? Did you wish for more recurring character appearances? And what was your favorite sketch this time around?

Alan Sepinwall may be reached at sepinwall@hitfix.com

Alan Sepinwall has been reviewing television since the mid-'90s, first for Tony Soprano's hometown paper, The Star-Ledger, and now for HitFix. His new book, "TV (The Book)" about the 100 greatest shows of all time, is available now. He can be reached at sepinwall@hitfix.com