A 2010 film directed by Steve Pink (the guy who did Accepted). Three friends (Adam, Lou and Nick), and Adam's nephew Jacob take a trip to a ski resort where Adam, Lou and Nick used to hang out to relive good times after Lou attempts suicide. However, while getting drunk in a hot tub, Lou spills some Chernobly (a type of Russian Red Bull) onto the hot tub controls, turning it into a time machine. The hot tub sends the four back to 1986, where Adam, Lou and Nick have regained their youth and replaced their 1986 selves. (Jacob, for some reason, is not a zygote. This goes unexplained, though he occasionally goes static like a television image with poor reception.)A hot-tub repairman (played by Chevy Chase), who may or may not be Mr. Exposition, occasionally drops by to have Cryptic Conversations about how to return to 2010 and the consequences of changing the past. This, however, doesn't stop the three from trying, much to the dismay of Jacob, who feels that their actions may put his very existence in jeopardy via the Butterfly Effect.
This film contains examples of:
Actor Allusion: One scene features the line: "I want my two dollars!" which is a reference to Better Off Dead, one of Cusack's earliest films (which also took place at a ski resort). Also on seeing all the drugs in Adam's suitcase, Jacob says "What are you, Hunter S. Thompson?" to which Adam replies, "I thought I was." John Cusack was close friends with Thompson, and attended his funeral. On a more meta note, Cusack had also campaigned for the role of the Thompson equivilant in Fear and Loathing in Las Vegas, a role that eventually went to Johnny Depp.
Dirty Communists: The time travelers are mistaken for these after Blaine and the ski patrol find their modern cell phones and MP3 players (which they think are spy gadgets), and their can of Chernobly.
The Eighties: Where our protagonists end up. Everything's so exaggerated, you can't tell whether for comedic purposes or because the characters are travelling back to their half-forgotten youth.
Historical In-Joke: The Red Bull-like Russian beverage "Chernobly" made the time machine work and brought the gang back to 1986 at the height of ski season, mere weeks prior to the Chernobyl incident.
I Choose To Stay: Lou. Adam also choses to stay behind, but ends up falling into the hot tub during the return trip. Lou was probably right to do so, since the other characters don't know about their exploits between 1986 and the present day.
It's Not You, It's Me: Played straight, both when Adam originally broke up with his girlfriend, and again in the Alternate Timeline when she dumps him, which she was gonna do anyway.
Knight Templar: Blaine and his ski patrol friends. They have a legitimate mission of maintaining law and order on the mountain, but they use this and the Red Scare as an excuse to be Jerkasses.
The Obi-Wannabe: The repairman delivers lots of cryptic and ominous-sounding warning, from which the gang infers that doing anything differently will screw up the timeline in unpredictable ways. They end up defying him, and it turns out to be 100% BS!
Pretty in Mink: Being the 80s, and in ski country, several ladies of course wear some fur coats, including one woman wearing her fur jacket open, with a bikini top underneath.
Ripple-Effect-Proof Memory: When the gang comes back to the future, they have no memory of Lougle or the success that they have enjoyed for the last few decades.
Rule of Funny: The overriding principle in the name of which all errors mentioned herein can easily be excused.
Running Gag: The bellhop repeatedly failing to lose his arm in situations where he should have.
In the deleted scenes, it's revealed that Miss Only-Does-Two-Guys-At-A-Time ensnared a significant percentage of the male cast during the night, but each time one of them running off.
Set Right What Once Went Wrong: What the guys end up doing once they summon up the brass to defy the repairman and do things the way they wish they had.
Also, while Adam is talking with the Manic Pixie Dream Girl in the house they broke into, a quick "Okay, so you're a Time Lord, and this hot tub is your space ship."
This scene is also framed like the final scene of "Sixteen Candles."
As noted above, "I want my two dollars!" is a reference to Cusack's early film Better Off Dead. (it's even mentioned as a DVD subtitle).
When Lou finally snaps and beats up Blaine it's an obvious (shot-for-shot and punch-for-punch) reference to a similar scene in "A Christmas Story."
And just before that happens, someone in the room shouts "Get a body bag!"
Nick: Somethin's goin' on in here. Dude is rockin' a cassette player. !
The Slow Path: Lou stays behind in the past to become rich and make sure that the events of this weekend propelled them into a Better Future. He suffers no ill effects because it is Mental Time Travel
Time Travelers Are Spies: One of the medics at the ski resort believes the main characters are Russian spies.
Time Travel for Fun and Profit: Lou, big time. To a lesser extent, all the time travelers, although they were not aware until they came back.
Trailers Always Spoil: Depending on which trailer you saw, one of them shows Violator aboard the huge yacht he bought himself after inventing Lougle, therefore spoiling the fact that he stays in the past. Nice.
Another trailer showed Jacob seeing his mother in 1986, and then shows her in bed with Lou saying "I feel pregnant."
Vomit Indiscretion Shot: A particularly nasty one. For extra credit bonus points, it hits a squirrel.
Wild Mass Guessing: See the Time Lord category for details (one of the few of these that isn't incredibly contrived).
Artistic License - History: Contrary to what the writers would have you believe, they had snowboards back in '86. Most ski resorts still didn't allow them, but being a ski patroller, Blaine could reasonably be expected to know what one is.
To be fair, Blaine isn't the brightest bulb on the tree, and a Deleted Scene has a skier tell Jacob that she's "never seen a real snowboard up close before."