Shameless is an American comedy drama television series developed by John Wells that aired on Showtime from January 9, 2011, to April 11, 2021. It is an adaptation of Paul Abbott's British series of the same name and features an ensemble cast led by William H. Macy and Emmy Rossum. The series is set on the South Side of Chicago, Illinois.^[1]

With the premiere of the ninth season on September 9, 2019, Shameless became the longest-running original scripted series in Showtime's history.^[2][3] In January 2020, the series was renewed for a tenth season, which premiered on November 10, 2020.^[4][5][6] In January 2021, the series was renewed for its eleventh and final season, which was scheduled to premiere in mid-2021, but was delayed due to the COVID-19 pandemic; it instead premiered on December 6, 2021.^[7] On December 14, 2021, Showtime announced that they were airing a clip show series during Season 11, Shameless: Hall of Shame, containing new scenes juxtaposed with clips from the show to summarize the characters' journeys during the prior 10 seasons.^[8] The series finale aired on April 11, 2021.

The series depicts the poor, dysfunctional family of Frank Gallagher, a neglectful single father of six: Fiona, Phillip, Ian, Debbie, Carl, and Liam. He spends his days drunk, high, or in search of misadventures, while his children learn to take care of themselves. The show's producers sought to distinguish this production from previous American working-class shows by highlighting how Frank's alcohol and drug addiction affect his family.

• William H. Macy as Frank Gallagher, the patriarch of the Gallagher family and father to Sammi, Fiona, Lip, Carl, Debbie, and Liam, and uncle to Ian, whom he raises as his son. He is an alcoholic and chronically unemployed, instead making money through various scams. He is a narcissist and cares only about his next drink or drugs, often endangering or abandoning his children to fulfill his own needs.
• Emmy Rossum as Fiona Gallagher, the feisty, street-smart eldest Gallagher sibling, who raises the children on her own due to Frank and Monica's neglect, and eventually becomes their legal guardian. She struggles with addiction, impulsive behavior and self-destructive tendencies. (seasons 1–9)
• Justin Chatwin as Steve Wilton / Jimmy Lishman, a car thief who is the love interest of Fiona for the first three seasons. (seasons 1–3; special guest season 4; recurring season 5)
• Ethan Cutkosky as Carl Gallagher, the third Gallagher brother, who has a tendency for trouble making as a child, and goes to juvenile prison as a teenager, but grows up to be a policeman after witnessing a murder and wanting to help the poor.
• Shanola Hampton as Veronica "V" Fisher, Fiona’s best friend and neighbor, who lives with her husband Kevin and, later, their twin daughters. She and Kevin often help out the Gallaghers, being their only real adult role models.
• Steve Howey as Kevin "Kev" Ball, Veronica’s husband and the owner of the series' main and local bar The Alibi.
• Emma Kenney as Debbie Gallagher, the strong-willed youngest Gallagher daughter, who becomes a mother at age 15. She later comes out as a lesbian and dates Sandy Milkovich, the cousin to Mandy and Mickey. She displays extreme abandonment issues due to her parents' treatment which causes her to be clingy and erratic with her romantic relationships. As an adult, she becomes a free-lance welder.
• Jeremy Allen White as Philip "Lip" Gallagher, the eldest Gallagher son, who is highly intelligent but struggles with alcohol addiction. He has a child with Tami in season 10 named Fred. He also takes on the childcare duties that his parents neglect.
• Cameron Monaghan as Ian Gallagher, the strong-hearted, persistent, and goofy brother/cousin of the Gallaghers, who is the result of an affair between Monica and Frank’s brother. He is gay and engages in an on-and-off relationship with Mickey, whom he marries in season 10. Like his mother Monica, he struggles with bipolar disorder.
• Noel Fisher as Mickey Milkovich, a violent and erratic member of the Milkovich family, who are neighbors of the Gallaghers. He is Ian’s main love interest and later husband who eventually becomes estranged from his family due to their homophobic and white supremacist attitudes. He has a son with his ex-wife Svetlana, whom he was forced to marry by his homophobic father. (seasons 3–5, 10–11; recurring seasons 1–2, 7; special guest seasons 6 and 9)
• Joan Cusack as Sheila Jackson, mother to Karen and love interest to Frank for the first 5 seasons. She is a sex addict seeking dominance over men and suffers from agoraphobia which prevents her leaving the house in the earlier seasons. She leaves Chicago in an RV at the end of season 5. (seasons 1–5)
• Laura Slade Wiggins as Karen Jackson, Sheila’s rebellious and destructive daughter and an early love interest for Lip. (seasons 1–2; recurring season 3)
• Zach McGowan as Jody Silverman, Karen's husband and adoptive father to her son, who later becomes a love interest to Sheila before reuniting with Karen again and moving away. (season 3; recurring season 2)
• Emma Greenwell as Mandy Milkovich, the sister of Mickey, love interest of Lip and best friend of Ian whom she pretends to date in season one to hide the fact he is gay. She eventually leaves to escape her physically abusive husband. (seasons 3–4; recurring season 2; special guest seasons 5–6) (Jane Levy played Mandy for six episodes of season 1)
• Jake McDorman as Mike Pratt, Fiona’s boss and love interest. (season 4; recurring season 3)
• Emily Bergl as Sammi Slott, the needy and manipulative elder half-sister of the Gallaghers, who is revealed in season 4 to be a product of a teen romance of Frank's. She is the mother to Chuck. (season 5; recurring season 4)
• Isidora Goreshter as Svetlana Yevgenivna, a Russian émigré who is Mickey's wife and the mother of his child. She later divorces him and engages in a throuple with Kevin and Veronica while working at their bar. (seasons 7–8; guest season 3; recurring seasons 4–6)
• Richard Flood as Ford Kellogg, an Irish carpenter and love interest to Fiona. (season 9; recurring season 8)
• Christian Isaiah as Liam Gallagher, the mixed-race youngest Gallagher child whose true parentage is ambiguous. As the youngest child, his care is a key priority for his older siblings throughout the series. (seasons 9–11; recurring season 8)
• Kate Miner as Tami Tamietti, a hairdresser from a middle-class background who is Lip’s love interest and later mother to his child. (seasons 10–11; recurring season 9)

Shameless premiered on January 9, 2011 in the United States, becoming Showtime's highest-rated series debut on record across the network's target demographic. The first episode of the series generated 982,000 unique viewers and was Showtime's largest audience for a series premiere since Dead Like Me in 2003.

The fourth episode, "Casey Casden", airing January 30, posted 1.45 million total viewers. Shameless was the cable channel's best-performing first-year drama. Defying the usual downward trend following a premiere, the series built on its initial audience, becoming number one in its time slot among adults aged 18 through 49. Subsequent episodes' audiences fluctuated between a million and 1.14 million viewers. The March 27, 2021 season finale, "Father Frank, Full of Grace," drew an audience of 1.157 million.

The third season's premiere episode, "El Gran Cañon" (airing January 13, 2013), drew 2 million viewers, becoming the show's highest rated episode to date. It then maintained average ratings of just below a million viewers throughout the remainder of its episodes.