The point of a TV spin-off is to give the audience more of what they like: the same thing, but different, like a movie sequel.
Well, usually. Sometimes the spin-off is a different kettle of fish entirely. Sometimes it's not even a kettle, and they're not even fish.
Here are seven spin-offs that went in very different directions to their parent series.
1. Pardon the Expression (spun off from Coronation Street)
Back in the early 1960s it wasn't Dad's Army that made Arthur Lowe a household name – he was famous for playing Coronation Street's stuffy retail manager Leonard Swindley. But when Lowe decided to quit the soap, the idea was sparked to carry him onto a spin-off series, a sitcom (complete with studio audience) titled Pardon the Expression which found Swindley now the deputy manager of a department store.
They made two series before Pardon the Expression itself was spun-off into sequel series Turn Out the Lights, an even more off-piste show which had Swindley (who by now was a professional speaker on astrology) travelling the country solving supernatural mysteries.
We're not making this up.
2. Baywatch Nights (spun off from Baywatch)
"Hey, I've got a neat idea for a Baywatch spin-off!" the pitch no doubt went. "Let's get rid of all the girls in bikinis and put David Hasselhoff in a suit and have him solve crimes!"
The muddle-headed thinking behind this epically misconceived spin-off soon saw Baywatch Nights drown in the ratings. Desperate to keep their show afloat, producers decided to retool it in its second year as a kind of Poundland X-Files, with Hasselhoff's Mitch Buchannon investigating sea monsters, demons and parallel universes. We eagerly await the Rock-fronted movie remake (not).
3. Trapper John MD (spun off from M*A*S*H)
In 1979, the Korean War-set comedy-drama M*A*S*H had been running for six years and was a ratings juggernaut for CBS. To capitalise, the network asked for a sister show from 20th Century Fox.
The resulting series, devised as a one-hour drama, focused on the character of Trapper John, three decades on from the TV series (and indeed the movie the TV show was spun off from), now played by actor Pernell Roberts. (Wayne Rogers had played him in the TV series, and Elliott Gould in the film).
Seeking royalties, M*A*S*H's producers (who were independent of CBS) took Fox to court, claiming the series was a spin-off of their show, but Fox insisted that it was a spin-off from the *movie*.
The court decided in Fox's favour and Trapper John MD went on to last seven seasons (that's five seasons more than M*A*S*H's "official" spin-off, the critically reviled AfterMASH).
4. Torchwood (spun off from Doctor Who)
Doctor Who had amazingly only spawned a single spin-off before Torchwood came along (the 1981 one-shot K9 & Company), but what made this one unique was that it wasn't chasing a family audience, but an adult one.
It was only a few minutes into its first episode that Torchwood dropped its first F-bomb, and suddenly we were in a new, darker, naughtier corner of the Whoniverse. It must be said, often the series felt like it was trying too hard to prove itself as Doctor Who's all-swearing, all-smoking, all-drinking cousin (see the "sex monster" of the series' second episode and Jack's rumpy-pumpy with Angelo in 'Immortal Sins').
So much so that when the two series did link up, it felt like an awkward collision of worlds.
5. Beverly Hills Buntz (spun off from Hill Street Blues)
Norman Buntz was one of the most popular characters on the gritty police drama Hill Street Blues, a seedy, morally questionable cop played with sleazy relish by Dennis Franz.
After that series climaxed in 1987 (with the last episode showing Buntz punching out his boss, Chief Daniels) came this curious comedy spin-off, which saw Buntz up sticks to Beverly Hills to become a private eye.
But where Hill Street Blues was showered with Emmys, Beverly Hills Buntz was so badly received that the network never even transmitted its final four episodes.
6. Grass (spun off from The Fast Show)
The Fast Show birthed a handful of spin-offs after it went off the air in 1997 (Swiss Toni, Ted and Ralph…), but the least known of all of them is probably Grass, a one-series sitcom centred around Simon Day's character, Billy Bleach, the tousle-haired pub know-it-all.
This low-key comedy saw Bleach relocated to Norfolk under a witness-protection programme after he chanced upon a gangland killing. Darker and more dramatic than you'd expect from something with Fast Show DNA, it's a bit of an obscure gem and deserves to be better known than it is.
7. Lou Grant (spun off from The Mary Tyler Moore Show)
We've seen comedy spin-offs from drama shows in this list, but not one that was a drama spin-off of a sitcom.
The Mary Tyler Moore Show was a critically acclaimed, awards-guzzling half-hour sitcom that was headlined by Mary Tyler Moore as Mary Richards, a producer on a network news show, with Edward Asner as her crusty boss Lou Grant.
The show bid its farewell in 1977 but it wasn't the last we'd see of Lou. A self-titled spin-off debuted just six months later, relocating Grant to LA as a newspaper editor. The one-hour drama went on to win almost as many plaudits as its parent show, with Asner scooping the Emmy for Outstanding Lead Actor in a Drama Series in both 1978 and 1980.
Its cancellation in 1982 was a surprise, especially to its star, who claimed his political activism was the real reason behind its out-of-the-blue axing.
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