While all of the proprietors of the pub in It's Always Sunny In Philadelphia have their quirks, Dennis Reynolds is the worst and likely even criminal.

Content Warning: This article contains mentions of sexual assault, violence and suicide.

FXX's It's Always Sunny in Philadelphia celebrates the best of the City of Brotherly Love. And while each of the proprietors of Paddy's Pub has their fair share of quirks, the worst of all of them has to be Dennis Reynolds.

Spoiled as a child and cultivated to have a false sense of superiority, Dennis has clawed for power at every opportunity, often sacrificing others (and his best friends) to get what he wants. While the gang, as a whole, has collectively done terrible things, there are plenty of things going on in Dennis's dark world that deserve another look. He's definitely the worst human being on the show, not to mention, a likely criminal.

10 Getting Revenge On The Environmental Activist

One of the best examples of how vengeful Dennis Reynolds can be is found in "The Gang Finds A Dumpster Baby." While the entire dumpster baby storyline was captivating enough, this episode also touched on environmental activism.

When Dennis tries to work alongside a local, activist group trying to save a tree, he's called out for his seasonal activism and made fun of by a hippie named Sage. Dennis doesn't take too kindly to this and operates an entire scheme to steal his girlfriend, trick him into chaining himself to a tree during a storm, and still get the tree taken down. Some would call that a hat trick of evil.

9 Stealing Brian LeFevre's Identity

In "Frank's Back in Business," Dennis shows Mac and Dee how to have a fun time stealing people's identities in one of the series' best B-plots. After Dennis takes a lost wallet found in the bar for himself, he sets out to see how long he can live that person's life without anyone noticing and how much he, Mac, and Dee can take from them.

Dennis has the ride of his life while he pushes Mac and Dee into increasingly more uncomfortable and precarious situations. Dennis would likely have done anything as Brian LeFevre, yet found the greatest satisfaction when he was inevitably caught and found out that Brian was actually dead.

8 Conspiring For Years To Exploit Frank

Dennis has had a not-so-secret rivalry going on with Frank ever since his ex-father purchased his bar. Since then, Dennis has reveled in either getting slight bits of power or manipulating Frank out of money and decisions.

However, the most devious thing he has ever done to Frank was to stage a years-long conspiracy to take the bar and his fortune away from him by faking some documents and making Frank believe that he had an illegitimate son (that wasn't Charlie). However, when Frank revealed that he wanted to run his empire with "Franquito," Dennis was quick to admit everything to maintain his relative bit of influence.

7 Spying On The Gang For Entertainment

In "Old Lady House: A Situation Comedy," Dennis revealed that he has several spy cameras that he's been storing and offers to use them to spy on Mac and Charlie's moms. Dennis is quick to turn the situation away from whatever Mac and Charlie needed and immediately uses the cameras to extend his own desires and sense of power and turns Mac and Charlie's moms' lives into a sitcom full of storylines and tropes.

However, when Charlie's mom discovers this, he presumably shuts down the operation because it is no longer fun for him. In actuality, he was just getting the gang to lower their guard so that he could spy on all of them once again, something that he has likely been doing for a while.

6 Abandoning His Son

In the season 12 finale, "Dennis' Double Life," Dennis reveals that he slept with a waitress when he was kicked off a plane in "The Gang Beats Boggs" and that same woman has now sought him out because she has had his baby. At the end of the episode, Dennis shockingly leaves the gang to give being a dad a shot.

This was to justify the fact that Dennis's actor, Glenn Howerton, wanted to take some time off to pursue other acting jobs, specifically to film A.P. Bio. However, when season 13 rolled around, he'd return once again (albeit in a noticeably diminished role) after deciding that it would be better to raise his kid from a distance.

5 Starting A Cult

In "Ass Kickers United: Mac and Charlie Join A Cult," Dennis reveals that he started an entire fake cult to get Mac to stop eating his Thin Mint cookies. Instead of just talking with Mac or hiding his food, Dennis starts a fitness-themed cult that was willing to hang on every word of his secret persona, The Master.

Dee and Frank would soon get involved to get the cult to do whatever they want, namely rebuild Mac and Dennis's old apartment and eat poop sandwiches. However, it's Dennis who takes things too far when, to flex his own influence, he tells the cult to end their own lives, which one unfortunate follower obeys without question.

4 Poisoning Mac With Diet Pills

Despite Mac and Dennis being longtime roommates and supposed best friends, the series has gone into greater detail within the past few years about how much Dennis actually hates Mac. At best, Dennis likely revels in how easy it is for him to get Mac to do things for him. However, he often just tolerates Mac as everything the pseudo-bodyguard does is either infuriating or inconvenient for him.

One of the ways that Dennis has tried to correct Mac to suit his liking in past years was by feeding him "size pills" so that he'd lose weight. Dennis didn't like having to look at Mac when he was going through his bigger phase, so he tricked him into taking an aggressive amount of diet pills, completely horrible to do to someone, let alone dangerous.

3 His Treatment Of Women

It's hard to think about Dennis Reynolds without thinking of all of the terrible things that he's done to women and there are many instances in the show that have alluded to his sexual assaults and even murder.

His grooming of young women, trapping others in secluded areas, his duct tape and zip ties, and many other hints are all not very subtle implications that Dennis is a criminal and a very dangerous person, and the "D.E.N.N.I.S. System" alone is enough to position him as a threat to all women. With his many bench warrants and everything else that's revealed about his character throughout the show, most viewers would agree that everything points to Dennis being a serial rapist and murderer.

2 Creating The Fake Seminar

Further to the above, while the series hasn't explicitly said that Dennis Reynolds is guilty of sexual assault, it's not as if his character ever attempts to avoid the accusation. In "Time's Up for the Gang," Paddy's Pub is forced to attend a seminar for bars deemed unsafe for women. The entire operation exposes Frank's workplace indecency, Mac's sexual aggressiveness, Charlie's stalking, and Dee's nonconsensual past with Charlie.

While this could have been a huge opportunity for the gang to actually grow as people, Dennis reveals in the end that he actually faked the entire seminar to help teach the gang (and everyone else in the room) how to better facilitate their sexual impropriety.

1 Trapping People In A Burning Apartment

In "The Gang Squashes Their Beefs," the gang invites all of their past enemies' friends to a Thanksgiving dinner to "squash their beefs." However, after their best intentions start falling apart and Frank sets a money fire, Dennis resolves to do the right and rational thing: trap everyone else inside his burning apartment.

After going as far as to drill nails to lock the door, Dennis tells the gang that everyone else can just leave through the fire escape. However, even if that were the case, it's a really aggressive move to not tell anyone about the fire, leave, and personally barricade the door. This fire would inevitably lead to another one of Rickety Cricket's injuries.

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