Hot Tub Time Machine is a comedy revolving around a time machine, as one might expect. It all starts with a group of guys who are fed up with their lives. The group is made up of Craig, a browbeaten husband, works at a pet place where he assists in exercising dogs and cleaning people's pets' behinds, Adam, who just got dumped from a serious relationship that he invested nearly all of his time in, Lou, an alcoholic party animal who just wants to be 19 again, and Jacob, who lives with his uncle, Adam, and does nothing but play video games in the basement. When the group is brought together when Lou is put in the hospital after he crashes his car, they decide that they should try to revive their lives by going back to the ski resort that helped to give Lou, Craig, and Adam some of the best moments. However, the resort ends up being depressing, worn down, and nothing like any of them remembers, only furthering their depression. But when they discover a hot tub, they have a night to remember as they let the machine relax their problems away, but when they when wake up later that morning in the same hut tub, they realize that somehow they time traveled to the year 1986 and are now their old selves again. 
 Hot Tub Time Machine is overall a really creative comedy that manages to provide scores of fun and entertainment. The whole thing manages to pack in jokes from left to right and from start to finish, and almost none of the jokes feel forced or overly-cheesy. Some of the humorous highlights are all of the scenes with an intriguing squirrel, and with an employee at the hotel that almost everybody should recognize from Back to the Future. 

 The visual effects of Hot Tub Time Machine aren't the greatest, per say, but they do manage to make the movie feel like an ode to the 80s, and these special effects truly make it seem like the main characters traveled back through time. The movie has a somewhat realistic feel, mostly due to the way the guys act as soon as they are given a chance to correct their mistakes, but parts of the plot are slightly flawed. For instance, it isn't quite clear how Jacob can exist in a past where he wasn't even born yet. 

 Hot Tub Time Machine tends to be a great hit with viewers, but critics weren't entirely pleased with this one. Rotten Tomatoes gave the movie a fair 63%, which isn't superb, but they are known to give comedies generally lower scores. IMDb gave the movie a 6.4/10, but a fairly high 90% of Google users liked the movie, demonstrating how viewers found the movie much more enjoyable than critics did. 

 Hot Tub Time Machine isn't the best movie out there, but it is an entertaining comedy that is sure to surpass some expectations and will definitely prove to be a good choice for people who are able to watch a movie with some explicit content.