All good things must come to an end; except, it seems, good television. Tonight, almost 20 years after the series officially ended, the long-anticipated prequel to Only Fools and Horses – voted Britain's favourite ever sitcom – will be screened on BBC 1.
It is one of the TV shows that refuses to die – instead of shuffling off the mortal screen, they are rejuvenated for decades. Other examples include Star Trek, Dr Who, Taggart, Top of the Pops and The Fall and Rise of Reginald Perrin.
In tonight's Rock & Chips, the BBC takes the saga of the lovable wheeler-dealer Del Boy back to the 1960s. Del and his friends, Trigger and Denzil, are teenagers, and Nicholas Lyndhurst, who played Del's gormless little brother, Rodney, in the original series, is cast as Freddy "the Frog" Robdal, the brothers' father.
Helen Wheatley, senior lecturer in film and television at Warwick University, said that television has now developed its own "canon" with programmes constantly being recycled as they are discovered by new generations of viewers.
"There have always been spin-offs as producers look for guaranteed audiences," said Dr Wheatley. "But it is also a particularly anxious time for television and viewers at the moment, with concerns that the internet is killing off the medium and its shared experience.
"The choice on TV is now almost overwhelming, so we reach for the familiar. Only Fools and Horses provides the same sense of pleasure as looking at an old family album. It's reassuring; it shows us how far we've come and taps into television's appetite for nostalgia."
The comedy, which reached 24 million viewers at its peak, ran for seven series between 1981 and 1991. Christmas specials kept viewers up to date with the goings-on in Nelson Mandela House until 2003.
The writer John Sullivan has nursed the idea of a prequel since 1997 but was distracted with The Green Green Grass, a spin-off featuring the rogue car trader Boycie and his wife, Marlene, who move out of Peckham to the countryside. The Independent on Sunday first revealed the prequel was in production last January.
"These shows also bring back the cosy glow that TV can create and reach across the generations," Dr Wheatley added. "I know someone whose five-year-old is a big Dr Who fan, and so they're working their way through the back catalogue together. It's a family activity."
First had children quivering behind the sofa in 1963 and broadcast original episodes until 1989. It was revived in 2005 to massive success – notably with David Tennant as the eccentric Tardis-dwelling Time Lord.
Ratings: 8/10 – Dalektable
Boldly went where no TV show had gone before in 1966 with a multi-ethnic cast and optimistic vision of the future. It also spawned four further original series over 40 years, not to mention numerous films, the last in 2009.
Ratings: 8/10 – Spocktacular
Top of the Pops
Thursday nights once revolved around chart acts miming to awkwardly dancing teenagers. It was axed after 42 years in 2006, the victim of the likes of MTV. But there's still Top of the Pops Two and Christmas specials.
Ratings: 5/10 – The beat goes on
This souped-up pub quiz has been giving smug students their comeuppance since 1962. The original series, hosted by Bamber Gascoigne, ended in 1987 but Jeremy Paxman revived it in 1994.
Ratings: 6/10 – No one likes a know-it-all
The tough Glaswegian detective has been solving grim murrrders since 1983. Not even the death of the lead actor, Mark McManus, in 1994 could stop the show which has broadcast original episodes every year.
Ratings: 7/10 – Longest-running 'polis' show
Grace, elegance and elephant-footedness have enthralled the viewing public since 1949. Broadcast on and off until 1998, the show was revived with a sexy makeover in 2004 as Strictly Come Dancing.
Ratings: 9/10 – The world's most watched show
Rab C Nesbitt
Gregor Fisher has been delighting Scottish – and bamboozling English – audiences with the happily unemployed alcoholic's Glaswegian patter since 1986. The sitcom ran until 1999 and was revived last week.
Ratings: 7/10 – Once a waster...
Only Fools and Horses
Who would have thought dodgy Del Boy would prove such a cushty character? This classic sitcom has seen original episodes on our screens for nearly 30 years as the writer John Sullivan feeds the nation's appetite for the Trotter family and its mishaps.
Ratings: 10/10 – Lovely Jubbly