Gavin & Stacey

• Gavin Shipman (Mathew Horne) – nicknamed "Gavlar", or "Gavalar" – the enthusiastic level-headed protagonist from Billericay.
• Stacey Shipman (née West) (Joanna Page) – protagonist from Barry.
• Neil "Smithy" Smith (James Corden) – Gavin's oldest and closest friend, lives in Billericay. Smithy gets jealous of Gavin and Stacey's relationship, and has a complicated relationship with Nessa. He fathers her child, Neil Noel Edmund Smith.
• Vanessa Shanessa "Nessa" Jenkins (Ruth Jones) – Stacey's oldest and closest friend, lives in Barry. Nessa has several celebrity connections, such as MP John Prescott, and later begins a relationship with Dave "Coaches" Lloyd Gooch.
• Michael "Mick" Shipman (Larry Lamb) – Gavin's down-to-earth father.
• Pamela Andrea "Pam" Shipman (née Gryglaszewska) (Alison Steadman) – Gavin's house-proud and over-protective mother.
• Brynfor "Bryn" West (Rob Brydon) – known as "Uncle Bryn"; Stacey's protective, naïve and eccentric uncle, and Gwen's brother-in-law. Bryn's brother, Trevor, Stacey's father, died prior to the time depicted in the series, which Bryn helped the family cope with. He has a difficult relationship with his nephew, Jason, due to something happening on their fishing trip. It is occasionally implied that he is attracted to men.
• Gwen West (Melanie Walters) – Stacey's caring, widowed mother. She also has an elder son, Jason, who lives in Spain.

Rob Brydon stars as Bryn

Alison Steadman stars as Pam

• David "Coaches" Lloyd Gooch (Steffan Rhodri) – local coach driver, later Nessa's fiancé. He is in the first episode when Stacey went to London to meet Gavin.
• Dawn Sutcliffe (Julia Davis) – a close friend of Pam and Mick, who frequently has public arguments with husband Pete.
• Peter "Pete" Sutcliffe (Adrian Scarborough) – a close friend of Pam and Mick, husband to Dawn, with whom he frequently has public arguments.
• Doris O'Neill (Margaret John) – Gwen's next-door-neighbour and close friend. The 2019 Christmas special refers to Doris: she died aged 84 and left her house to Gavin and Stacey. Nessa is contesting the legacy through the courts.
• Jason West (Robert Wilfort) – Stacey's gay older brother, who lives in Spain.
• Ruth "Rudi" Smith (Sheridan Smith) – Smithy's immature, but loving, younger sister who also likes to be called "Smithy'". She works at a fast food restaurant in Billericay.
• Catherina "Cath" Smith (Pam Ferris) – Smithy and Rudi's single mother, who suffers from "a mild form of narcolepsy" (which Pam thinks is a cover for a drinking problem).
• Dirtbox (Andrew Knott) – a friend of Gavin and Smithy.
• Deano (Mathew Baynton) – a friend of Gavin and Smithy, who works with Smithy as a builder and appears to be very dim-witted.
• Karl "Budgie" Barratt (Russell Tovey) – a friend of Gavin and Smithy.
• Chinese Alan (Dominic Gaskell) – a friend of Gavin and Smithy, he enters the room with the catchphrase "Did someone order a Chinese?" - despite not actually being Chinese.
• Craig "Fingers" (Samuel Anderson) – a friend of Gavin and Smithy, who has an on/off relationship with Stacey's friend Louise, after they meet at the wedding and have sex in a back room.
• Jesus (Daniel Curtis) – a friend of Gavin and Smithy, who Smithy insults on Gavin's stag night, claiming he had to get his T-shirt made at the last minute.
• Gary Finch (Jason Gregg) and Simon – friends of Gavin and Smithy, who are never just Gary or Simon.
• Swede (John Grisley) – a friend of Gavin and Smithy.
• Louise Evans (Ffion Williams) – a friend of Stacey and Nessa, who has an on/off relationship with Gavin and Smithy's friend Fingers, after they meet at the wedding and have sex in a back room.
• Angie (Beth Granville) – a friend of Stacey and Nessa.
• Neil Jenkins (Huw Dafydd) – Nessa's father, rarely seen in Barry, but attended Neil the baby's christening.
• Owain Hughes (Steve Meo) – Website Manager in Gavin's new job in Cardiff. He has the confusing catchphrase: 'Owain Hughes, and before you ask, no I don't'.
• Dick Powell (Gwynfor Roberts) – the only fully Welsh-speaking inhabitant of Barry (aside from the Welsh nationalists in the caravan park), he works on the black market selling meat.
• Neil "the Baby" Noel Edmond Smith (Scarlett Humphreys;[8] 2008, Lewis Marchant; 2008, Rocco Romanello; 2009, Ewan Kennedy; 2009, Oscar Hartland; 2009, 2019) – Smithy and Nessa's son. He is named after Nessa's father and Smithy (who are both called Neil), Nessa's friend from Hear'Say (Noel Sullivan), and Smithy's grandfather Edmond. In the episode of the christening, Gavin humorously says that Neil is named after Noel Edmonds, which Smithy gets annoyed over.
• Harri Shipman (Gabriel Mitell) - Gavin and Stacey's eldest child, who was born shortly after the third series in 2010.
• Caitlin Shipman (Martha Tregonning) - Gavin and Stacey's elder daughter.
• Megan Shipman (Maddison Belle Platt) - Gavin and Stacey's younger daughter.

Noel Sullivan and John Prescott made brief cameo appearances towards the end of the final series.[9][10]

The initial series begins with the lives of the title characters, Gavin Shipman (Mathew Horne) and Stacey West (Joanna Page). Gavin is 28 and lives at home in Billericay, Essex, with his parents, Mick (Larry Lamb) and Pam (Alison Steadman). He and Stacey, along with their respective best friends Neil "Smithy" Smith (James Corden) and Nessa Jenkins (Ruth Jones), go out on a double date. The night ends with Gavin and Stacey returning to a hotel room and sleeping together, as do Smithy and Nessa. Gavin and Stacey become infatuated with each other, but Smithy and Nessa are happy to forget their drunken one-night stand and make little contact with one another afterwards. In the rest of the series, Gavin and Stacey continue their long-distance relationship before becoming engaged and getting married on 6 April 2007. The series ends with Nessa going to inform Smithy that she is pregnant with his child but changes her mind at the last minute.

The second series begins with the newlyweds arriving from a honeymoon in Greece. The in-laws meet again at the Shipmans' house in Essex, where Nessa has some shocking revelations – especially for Smithy, who learns that she is pregnant with his baby, and although he makes it clear he thoroughly dislikes the woman, he is generally civil and supportive towards her about their child. Meanwhile, Gavin and Stacey, living at Pam and Mick's house, run into trouble when Stacey struggles to find a job and becomes home-sick for Barry and her family. The couple try to overcome their problem by looking for an apartment or house in Essex, but Stacey is still dissatisfied and is considering moving back to South Wales to be with her family. In the final episode of the series, Stacey takes off her wedding ring, much to the upset of Gavin, but this is interrupted by the news of Nessa unexpectedly going into labour a month early. Pam, Mick and Stacey hurry across to Wales, whilst Gavin rushes to find Smithy with Smithy's sister, Rudi (Sheridan Smith), eventually finding him in the pub watching football. They arrive to find that Nessa has given birth to a boy, Neil. Gavin and Stacey decide to put their differences aside and are together once again.

An extended Christmas special involves Stacey's family, along with Nessa and her partner, Dave Coaches (Steffan Rhodri), spending Christmas with Gavin's parents. Gavin reveals that he has found a job in Cardiff, which at first causes upset for Pam and Smithy, but they both learn to accept it. Gavin later admits to Smithy that he is moving to Barry with Stacey in order to save his marriage. Smithy also gets upset when he feels that Dave, who lives with the baby, Neil, is replacing him as a father. Smithy is furthermore unhappy after Dave proposes to Nessa (with the ring enclosed in a cigarette packet), and she accepts.

Gavin begins on his new job in Wales and his parents and Smithy travel to Wales for Neil's christening. In the next episode Gavin and Stacey, and Nessa and her child Neil, spend the weekend at Pam and Mick's, and after a drunken night, it is believed that Nessa and Smithy may have once again had sex after waking up in bed together the next morning. Gavin and Stacey begin trying for a baby and Stacey is upset and disappointed when she learns that they may not be able to have children. Gavin becomes depressed and preoccupied with this issue, and in an attempt to cheer him up, Pam, Mick and Smithy arrange a surprise trip to Barry beach on a sunny bank holiday. Nessa and Dave also run into trouble after Dave learns about her alleged sexual intercourse with Smithy, but the two decide to go ahead with the wedding. In the final episode, Stacey discovers she is pregnant after all, and the couple are overjoyed and excited. Smithy shows up at Nessa and Dave's wedding ceremony with Neil, pleading for her not to marry him, and accusing her of not loving Dave. Dave, much to everyone's surprise, agrees with Smithy that Nessa does not love him, and the ceremony is called off. The series ends showing the four (Gavin, Stacey, Nessa and Smithy) six months later on Barry beachfront, with a visibly pregnant Stacey.

In May 2019, Corden announced that he and Jones had written a Christmas special. The programme aired on BBC One on 25 December 2019. The episode started off with Gavin and Stacey, who now have three children, and are living in Barry next door to Stacey's mum after Doris - who died several years before - left them the property in her will. Nessa and Smithy's child, Neil - still known as "Neil, the Baby” - is now eleven. Smithy has started a new relationship with Sonia (Laura Aikman) and he plans to propose to her on Christmas Day. Gwen, Bryn & Jason join together to celebrate the holiday, together with Pam and Mick, who spent Christmas Eve with Dawn and Pete. At the end of the episode, Nessa tells Smithy that she loves him, and she proposes.

Immediately after the end of series 2, in April 2008 The Guardian described the show as the "BBC 3's biggest breakout comedy hit since Little Britain", while Deborah Orr wrote that the show was "amiable, unpretentious, well-scripted, nicely acted and archly amusing. It's a good series, taking its place in a well-worn comedic progression, stretching back to The Liver Birds".[15][22]

Just before the third series aired, The Independent described how the show had developed from a respectable début on BBC Three to an award-winning show with mainstream popularity after the BBC One Christmas special, although it noted a perception from some that the show shouldn't "get above itself". With its mainstream acceptance, however, it was of the opinion that the show had all the ingredients to become an "audience-pleasing family sitcom in the tradition of Only Fools and Horses and The Royle Family – churning out series after series and Christmas special after Christmas special", although by then, the writers had already ruled out future full series.[23] In 2019, Gavin & Stacey was named the 17th greatest British sitcom of all time in a poll by Radio Times.[2]

In the fifth episode of the second series (6 April 2008), for Gwen's birthday barn dance, Bryn and Nessa perform a duet of "Islands in the Stream". On 21 February 2009, this was adapted into "Barry Islands In The Stream", a musical mini-sketch aired for Comic Relief. In a storyline that sees Bryn and Nessa invited to compete in the World Karaoke Championships in Las Vegas, Nessa bumps into her old friend Tom Jones, who joins them on stage, and the sketch also features Bee Gee Robin Gibb. Also released as a charity single, it debuted in the number one spot on the UK Singles Chart on 15 March 2009.[24]

For Red Nose Day 2009 on 13/14 March, the main telethon event for Comic Relief, a second sketch was aired where James Corden, in character as Smithy, has a chance encounter with the England national football team and proceeds to give them some advice on tactics and teamwork. "Barry Islands In The Stream" was also performed live for the Top of the Pops 2009 Red Nose Day special.

There have been two charity episodes depicted as a "spin-off" of Gavin & Stacey called Smithy, starring James Corden as the title character.

For Sport Relief 2010 on 19 March 2010, Corden appeared again as Smithy in a long sketch about coaching, where he meets England footballers such as David Beckham, John Terry and Rio Ferdinand. Corden had previously recorded a live 9 minute segment during the December 2009 BBC Sports Personality of the Year awards ceremony. It sees Smithy being presented with the Coach of the Year Award for his unsung coaching influence on several British sports stars. As he jokes with the audience he declares he can't accept the award, and goes on to rant at the assembled sporting stars for having 'lost their way' and focusing on celebrity, ending on a rousing appeal to get back to basics, leaving hosts Sue Barker and Gary Lineker in mock tears. As a backstory, sketches are shown of how Smithy coached Tom Daley, Andrew Flintoff, Andy Murray, Jenson Button, David Beckham and the Manchester United team.[25]

On 19 December 2010, Corden appeared as Smithy in the live ceremony for the 2010 BBC Sports Personality of the Year Awards, announcing that Sport Relief had raised over £44m, expressing his doubts that England manager Fabio Capello would win the coach of the year award, and giving the 15 times Darts World Champion Phil Taylor his backing as a candidate for the main award, praising his dedication to training by going down the pub every night sinking pints.

There was another episode of Smithy for the 2011 Comic Relief appeal guest starring Lenny Henry, Richard Curtis, George Michael, Dermot O'Leary, JLS (Aston Merrygold, Marvin Humes, Oritsé Williams and JB Gill), Davina McCall, Rupert Grint, Tom Felton, Sebastian Coe, Gordon Brown, Robert Winston, Roger Lloyd-Pack, Rio Ferdinand, Keira Knightley, Richard Madeley, Clare Balding, Tom Daley, Justin Bieber and surviving Beatles Paul McCartney and Ringo Starr.

Corden appeared as Smithy again on Michael McIntyre's Christmas Roadshow on BBC One on 25 December 2011. The sketch showed Smithy in a dating-show style spoof with Miranda Hart as her TV alter ego.

He again appeared at Comic Relief, this time in 2013, in the live studio itself. He went on to rant about all the world's issues and his opinions on them.

Corden appeared as the character again for 2016's Sport Relief, where Smithy campaigns to be elected as Sepp Blatter's replacement as the president of FIFA.

On 30 March 2010, Corden and Jones appeared in character as Smithy and Nessa as part of Channel 4's Comedy Gala, held at the O2 Arena in London in aid of Great Ormond Street Children's Hospital, broadcast on Channel 4 on 5 April 2010. Following on from the events of the final episode, they arrive in London on a day trip from Barry Island, with Neil the baby in tow.

In March 2008, it was reported the American network NBC had bought the rights to produce an American remake from Baby Cow Productions. Initial ideas according to Corden were to have Gavin coming from New Jersey and Stacey from South Carolina, meeting up in New York City.[11] In December 2008 however, Jones stated "There was a script written for NBC. They optioned it, but then that went away. I read the script and it wasn't great to be honest with you. But now ABC are looking into writing a pilot and hopefully that will work out".[27] At the time, both Corden and Jones were reportedly acting as executive producers of the ABC version, while interviewing other people for the job of writing the adaptation.[28]

In September 2009 it was reported that ABC had ordered a pilot for an American remake, to be written by Stacy Traub and Hayes Jackson, and produced by BBC Worldwide.[29][30] The series was not picked up.

On 8 May 2013, Fox announced that an American remake, Us & Them, would be broadcast in the network's 2013–14 schedule. Thirteen episodes were ordered. On 11 October 2013, it was revealed that only 6 episodes would air after production went into early hiatus, a hiatus which then became permanent.[31][32] In June 2014, Fox announced that the 6 episodes would not air on the network.[33]