- Big-Lipped Alligator Moment: In the first episode following baby Stella's birth, there is a storyline which involves her communicating telepathically with Frank and Monica. Random, stupid, makes no sense even in context, and after that one episode, nobody mentions the incident again.
- Broken Base: Nearly everyone agrees that the show has undergone serious Seasonal Rot as it went on and eventually the writers lost sight of the original point of the series. The point where it becomes unwatchable, however, is hotly debated: common turning points cited include the end of Series 2 (where Steve and Fiona leave the series), Series 4 (where the series has a reboot, the Maguires join the cast as regulars, and many more major characters leave), Series 6 (where the Cerebus Syndrome starts kicking in full force and crosses the line into dark dramedy, as well as more characters leaving), and Series 8 (where overarching plotlines are done away with, humor becomes cheap, character development reaches new levels of inconsistency, and the vast majority of the original cast have left).
- Critical Research Failure: When Frank is ranting about his children having been a burden to him in the last episode of Series 11, he uses Socrates, Alexander the Great, Julius Caesar and Leonardo Da Vinci as examples of men who were not "stupid enough" to have any kids. All of them had either biological or adopted childrennote .
- Ensemble Dark Horse: Lillian, a supporting character who is incredibly popular with fans despite her limited screentime.
- Moral Event Horizon:
- In Series 2, Frank agrees to take care of an expired friend's dog. Cut to him on a bridge luring it into a sack with some meat.
- Throughout Series 2 Episode 1, where Frank's dad Neville makes an appearance, he persistently belittles Frank and puts pressure on him to man up to his responsibilities as a father and do something with his life. Fair enough, you'd think. Then he beats Frank, and it's heavily implied he did it regularly while his son was growing up. Well, Frank did neglect said responsibilities again to go drinking and partying in the pub by himself at midday. Maybe it's excusable... a bit. But then he finally crosses this by shaking a ladder that Frank was on, saying he wished he'd killed Frank at birth.
- Monica is a terrible person. She left her children and caused Frank to become the mess that he is now (not to mention apparently was abusive towards him prior to leaving), and acts selfish and self-serving, as well as giving terrible advice to her children. However, she doesn't truly become an irredeemable person until the beginning of one episode in the later seasons when, after the rest of the family hide Liam's trip to Blackpool to star in an ad, she takes their pet mouse and sticks it in the microwave and threatens to turn it on until they tell her. When they begin to do so, she still edges towards pressing the button just to get more details.
- Nightmare Fuel: Jamie digging up Joe's dead father's corpse and dumping it outside his shop at the end of Series 7.
- Paddy Maguire being tied to a bed for days on end and being turned into a heroin addict.
- Rescued from the Scrappy Heap: Kelly Ball started life off as Kev's annoying sister. After annoying the hell out of everyone in one episode per Series (2-4), she was promoted to the main cast as Shane Maguire's girlfriend and has shed her previous image.
- Retroactive Recognition: The actor who portrayed Steve is now known to international audiences as the younger Professor X in the X-Men Film Series.
- Seasonal Rot: Critics and fans alike agree that Shameless gets shakier and declines in quality as it goes along. See Broken Base above.
- Strangled by the Red String: Kelly and Marty barely speak to each other in the early series, yet by series 9 when Marty returns, he suddenly announces he loves her and even stranger, she seems to return the feeling despite being married to Shane for years.
- Prior to that, we had Tom and Debbie's relationship. Tom had an episode which seemed to be building a relationship with Mandy; instead, he reveals in the last few minutes that he has a girlfriend, who's revealed to be then-underaged Debbie, the two both saying how much they love each other. This was to set up a storyline where the two break up and, his very poor reaction to it leading to him eventually being dismissed from the police and having to leave in order to avoid punishment.
- They Wasted a Perfectly Good Plot: Lip returned towards the end of Series 11 for an episode, and they seemed to be building up a plot about how he was struggling to raise and provide for Katie despite the "new life" he thought he'd eventually achieve by going to university (and for those who graduated in the past 15 years or so, especially after the recession hit in 2008, this is an all-too familiar story). However, the episode focuses more on Lip's strained relationship with Frank and that side plot just fizzles out.
- The Woobie: Fiona. Forced to grow up and take care of her family because her parents were either physically or emotionally neglectful, all the while being picked on at school for being dirt poor. Eventually she falls in love with Steve, but he's forced to leave her when they get engaged due to accidentally killing a drug dealer in self defense and being tied to the scene, her family then has to deal with legal troubles, including having every penny they have stolen by a corrupt cop. She gets pregnant from a one night stand, resulting in her having to pick between running off with Steve and living with the baby's father. At least she got to leave Chadsworth.
- Tom. As revealed, he grew up without any parents in an orphanage, became attracted to his co-worker only for her to use his feelings to manipulate him a few times, was able to track down his birth mother only to discover she'd already died, he fell in love with a girl who was too young, and once she was old enough she broke up with him when he asked her to move in with him. To top that off, he spent the rest of the season being called a stalker or creep whenever he ended up in the same room as Debbie and her friends, before being fired after his prank on Stan as payback for Stan's own pranks leading Stan to claim compensation, and him having to leave to avoid being punished for all this.
YMMV / Shameless (UK)