As South Park's Butters discovered in 'The Simpsons Already Did It', all the best ideas in the world have probably been done before by someone else.
And thus, with every new TV show that gets made, there's a big chance that someone will notice certain similarities. That's what 80+ years of television does to you.
These are the times when eyebrows were raised…
1. True Detective
Accused of copying: Horror author Thomas Ligotti
HBO's True Detective is considered among one of the greatest crime dramas of all time (well, the first season at least), but some viewers had noted certain similarities between lines spoken by Matthew McConaughey's Rust and quotes in a certain supernatural horror book.
Now, not everyone is clued up with the work of Thomas Ligotti, but the lines were so similar, that creator Nic Pizzolatto had to respond to claims that he outright stole them out of The Conspiracy Against the Human Race.
Pizzolatto denied the claims, but admitted that Ligotti had been a huge influence on him. When asked about the subject of hardboiled detectives, he said: "What could be more hardboiled than the worldview of Ligotti or [Emil] Cioran?"
2. Downton Abbey
Accused of copying: Upstairs, Downstairs
The original version of Upstairs, Downstairs was a huge hit in the 1970s and centered around the lives of servants and masters in a large Edwardian manor.
Cut to 2010, and Julian Fellowes released Downton Abbey to the world, and it was also a huge success. Oh, and it also centered around the lives of servants and masters in a large Edwardian manor.
Upstairs, Downstairs creator Jean Marsh was not impressed. Especially as she had been trying to launch a revival of her show on the BBC for yonks. And then when they finally did, it looked like they were the ones copying Downton Abbey (lampooned to hilarious effect in the Fast Show clip above).
"I think we were all surprised," Marsh told The One Show. "The new Upstairs, Downstairs had been in the works for about three years. We were trying to sort out 40 years of rights and then it also started – Downton Abbey – in the Edwardian era, which Upstairs, Downstairs did. So it might be a coincidence and I might be the queen of Belgium."
3. Dinosaurs
Accused of copying: The Simpsons
If you were going to accuse 1990s puppet sitcom Dinosaurs of copying anything, it would surely be The Flintstones, right? But the guys behind The Simpsons reckoned it closer resembled their work, but set in prehistoric times.
The Simpsons joked about the similarities in one particular episode, noting how the show featured a rebellious young son with spiky hair, a mischievous baby and a grouchy dad.
"It's like they saw our lives and put it right up on screen," a meta Bart says. Just wait until they catch Family Guy for the first time.
4. Red Dwarf
Accused of copying: Star Trek: The Next Generation
Yes, on paper, this sounds ridiculous. But this kind of strange accusation of plagiarism came direct from Sir Patrick Stewart, himself.
The clip above shows how Patrick first caught the BBC sci-fi sitcom Red Dwarf over in the States, and was immediately calling his lawyers when he thought it was a complete ripoff of TNG.
We reckon he was talking about the Dwarf episode 'Gunmen of the Apocalypse', which sent the boys to a Western-style video game. Just a year earlier, Patrick had directed a similar TNG episode, in which the crew enter a Wild West holodeck world.
Thankfully, Sir Pat instantly realised he was wrong and ended up becoming a huge fan, even hosting a special 'Red Dwarf Night' on BBC Two several years later.
5. Key & Peele
Accused of copying: Chappelle's Show
Dave Chappelle's acclaimed sketch show was a huge success for Comedy Central in the early 2000s, but he sadly departed the series after just three seasons.
After years of the channel trying to replicate Chappelle's brand of adult humour, featuring skits mixed with live stand-up, Comedy Central finally found a worthy successor nearly 10 years later in Key & Peele.
Jordan Peele and Keegan Michael Key's sketch show also featured stand-up elements and included many of the same themes as Chappelle's Show, but was arguably even more popular and critically acclaimed with the social media generation.
After making his big show business comeback, Chappelle revealed that watching Key & Peele made him upset. "Put some respect on my name, y'all don't know what I've been through, watching Key & Peele do my show the last five f***ing years," he said at a festival in 2016.
Clarifying his comments on CBS a year later, he said: "I fought the network very hard so that those conventions could come to fruition. So, like the first episode I do, that black white supremacist sketch. And it's like, 'Well, that's 10 minutes long. It should be five minutes long.' Why should it be five minutes long? Like, these types of conventions. I fought very hard.
"So when I watch Key & Peele and I see they're doing a format that I created, and at the end of the show, it says, 'Created by Key & Peele,' that hurts my feelings."
