4 O'Clock Club is a British comedy drama[1] and musical children's television series set in a secondary school, which premiered on 13 January 2012[2] on CBBC.

The first series centres on Josh Carter (Khalil Madovi), a pupil at Elmsbury High, and his older brother Nathan (Ben Bailey “Doc Brown” Smith), who works as a teacher there.

Josh is portrayed as a laid-back teenage schoolboy trying to maintain his cool reputation, while also being rebellious and trying to cause trouble in order to achieve his goals and humiliate or outsmart Nathan.

In the second series, Nathan leaves Elmsbury to go to Scotland and new music teacher Dexter Harris (Jason Callender) joins the school.

Issac (Layton Blake) made a guest and a 1st appearance in Series 2 Episode 1 but his name wasn't confirmed and the credits say "Fowlmere Josh".

Due to the merger, several new characters joined the series in episode three, these were PE teacher Mr Nunn (Dan Wright), Miss Parkwood (Sophia Di Martino) and pupils in Nero's year; Eli Grant (Daniel Kerr), Owen Garland (Lewis Brindley), Fleur Murphy (Chloe Davison) and Eleesha Rahad (Grace McIntosh).

The series also introduced a new main character, rebellious and cynical tomboy Clem Burton (Jade Alleyne), who joins Nero's crew as well as mysterious spray paintings of Andress appear around Elmsmere, called 'The Phantom Sprayer', however it was later revealed that it was Mr Bell who was the criminal.

In the fifth series, all the characters from the fourth series remain apart from Miss Andress, but with three new characters, Lizzie's younger sister Amber (Ella Marshall Pinder) and her friends Violet (Cara Jenkins) and Darnesh (Riley McCormick) who want to fit in with the "cool" kids, like Nero and his gang.

Zoe-Marie's younger sister Ingrid (Zara Thurstan) also starts at the school and quickly becomes Amber's enemy.

In the sixth series, Nero and Clem have finally begun dating after their summer romance, but eventually break up after several arguments.

Mr Bell becomes stand-in headteacher, while Helena Goodman takes time off to reflect on the financial issues of the old site.

The eighth series began with a special for Christmas on 19 December 2018, focusing on Mr Bell and his relationship with his son CJ.

New music teacher Clinton Russell (Andy Umerah) was introduced as well, who replaces Danny, and also dates PC Rowe.

This series saw the final appearances of CJ and Crispin Bell (Rufus King-Dabbs and Simon Lowe) in episodes 4 and 10 respectively and Owen (Lewis Brindley), Fleur (Chloe Davison), Eleesha (Grace McIntosh), Katie (Jasmine Payne), Polly (Mischa Taylor Eckersley) and Evan (Zak Sutcliffe) in episode 13 as they left sixth form.

Set during the end of term at Elmsmere, it focuses on Crispin Bell, filming a documentary with the help of Fleur Murphy.

As of the seventh series, the show is filmed in the former site of St George's Roman Catholic High School in Walkden.