The biggest challenge for the new Star Wars was to make us love Rey and Finn as much as Luke and Han. Mission accomplished! But most of the time, when a venerable franchise introduces new characters, it's a horrendous failure. Here are 10 long-running series that actually made us care about new characters. There are plenty of lists cataloguing the times that a series added a brand new character who ruined everything. The Scrappy Doo effect. But what about the cases where new characters (or a whole new cast) came along and everyone embraced them?
Here are our picks, in no particular order:
1. Donna Noble on Doctor Who
This show has survived for 50+ years, in large part, by adding new supporting characters every year or two. But Donna was the textbook example of a new character who stole everyone's heart and captured our imaginations. Even if we kind of hated her at first.
2. Imperator Furiosa in Mad Max: Fury Road
Sorry, she's just on our minds right now. She's still our favourite new character of 2015, and we kind of want another Furiosa movie more than another Mad Max movie.
3. Anya on Buffy the Vampire Slayer
She came along pretty late in the show's run, considering, and unlike some other other late additions (cough, cough, Dawn) she became one of our favourites among the Scooby Gang. I still think Xander should have married her.
4. Ahsoka Tano in Star Wars: The Clone Wars
This could have gone so horribly wrong. Adding a previously unknown character who studied with Anakin between Attack of the Clones and Revenge of the Sith was a terrible idea, on the face of it. But she turned out to be one of the best things ever to happen to Star Wars, and even made Anakin way more interesting.
5. Rodney McKay in Stargate
We still have a shrine in our hearts to the chatty, uber-geeky, sometimes arrogant Canadian who joined SG-1 and then ruled the spin-off, Atlantis.
6. Root and Shaw in Person of Interest
It's almost hard to remember at this point that the psycho hacker and the psycho killer weren't part of this show's cast from the beginning. They were relatively late additions, especially Shaw, but at this point they're the heart of the show.
7. Queen Divine Justice in Black Panther
This wise-cracking Chicago teen who turnes out to have a vitally important family legacy was introduced relatively recently, during Priest's indispensible 1990s run. And she's now our favourite supporting character in the Black Panther cast. Let's hope she turns up in the movie!
8. Stephanie Brown in Batman
The 1990s were full of new characters being added to your favourite comics, and most of them were total losses. But Stephanie Brown, aka Spoiler, is one of the most interesting characters in the Batman mythos at this point. The daughter of a supervillain, she hates secrets and lies, and wants to make things right. Plus in this day of intense spoiler-phobia, having a vigilante named "Spoiler" is kind of perfect.
9. Henry Jones, Sr. in Indiana Jones and the Last Crusade
This is another thing that could have turned out abominably. Indiana Jones is one of those characters who's pretty much perfect and fully formed — so let's introduce his semi-estranged father! Ugh, no. But the combination of witty writing and Sean Connery's chemistry with Harrison Ford makes this the best thing ever.
10. Castiel and Crowley in Supernatural
Again, these characters were introduced relatively late in the show's run — towards the tail end of creator Eric Kripke's tenure, anyway. But this rebel angel and scheming demon basically became key members of the supporting cast. And they're a great pairing, whenever they have to work together. Even if the show did sort of run out of things to do with them after a bit.