The premiere of a series following the escapades of a hard-partying Chicago father (William H. Macy) who provides no guidance to his dysfunctional brood of six. First up: daughter Fiona has her purse snatched but manages to make the acquaintance of a handsome young man, and Lip discovers an unsettling secret about younger brother Ian.
A manhunt goes out for Frank after he heads off on a Friday bender and uncharacteristically fails to show up to cash his disability check. Later, he turns up in Toronto with no memory of how he got there.
Fiona contemplates romance with a policeman who has had a lifelong crush on her, but Steve isn't about to remove himself from the picture. Meanwhile, Ian spurns a girl's attentions and her brothers come looking for him; and elderly Aunt Ginger, who actually owns the Gallagher house, goes missing and the whole family joins in the search.
When Aunt Ginger takes her leave, little Debbie is left sad and lonely, so to ease the hurt she kidnaps a toddler from a birthday party, leaving the Gallaghers scrambling to come up with a plan to return the child before the Chicago Police Department fingers them for the crime. Meanwhile, Frank parries sexual advances from Karen, while Kevin's white lie involving his noninvolvement with an attractive young lady leads to a surprising conclusion.
The family attempts to pull off a fake wedding when it is revealed that Veronica comes from a wealthy family; Frank is given bad medical news and doesn't do such a good job of handling it; and Steve goes cruising for a new car, with Fiona along for the ride.
Fiona scrambles to spruce up the house for an impending visit from Carl's teacher; Lip makes some extra cash by taking tests for his less-intelligent classmates; the Kash and Grab is repeatedly robbed by a local punk; and Frank's lack of business acumen costs him.
To come up with $6000 Frank owes to two thugs, he entertains the notion of a risky business that's going to require some big-time help from the family. Elsewhere, Ian stands up to a bully, and Fiona agrees to go away with Steve, leaving Liam with agoraphobe Sheila.
Frank goes on the wagon, which pleases Carl and Debbie, but a skeptical Lip doesn't believe their father's newfound temperance will keep him from the bottle for long. Elsewhere, Fiona scrambles to find a better-paying job, which leads her to overlook some suspicious behavior of Steve's; Kev and Veronica open their house to a foster child and get quite a surprise when they learn her family history; Ian pursues Mickey; and Sheila worries Frank has lost interest in her.
Frank is in line for some settlement money, but there's a catch: he needs his ex-wife's signature on the paperwork. Elsewhere, Debbie discovers a secret about Steve; Monica turns up and announces she's taking baby Liam with her; and an angry Fiona moves out of the house and in with Steve.
Monica returns and the Gallagher clan are in a tizzy as they try to determine if Frank is their real father. And Fiona, who is thoroughly disgusted with Monica, decides to move in next door with Steve. Meanwhile, Eddie invites Karen to a Purity Ball; and Frank uses Carl in an effort to thwart a disability worker's attempt to pull the plug on the state funds he receives.
Fiona befriends an alluring young lady after Debbie talks her into joining a mothers' group. Elsewhere, Tony suspects he knows the truth behind Steve's car-stealing business; Lip and Ian try to learn which of their uncles is Ian's dad; and Frank sees his workman's compensation benefits come to an end, so he sends the kids on a mission to find him a job, preferably one that is highly dangerous.
In the Season 1 finale, Steve's actual occupation is revealed and he tries to persuade Fiona to leave town with him. Meanwhile, Frank goes into hiding when his and Karen's secret is spilled; and car thieves Lip and Ian get caught and locked up, and it's up to Fiona to figure out how to spring them.