Whether you love them or hate them, sequels are the bread and butter of Hollywood. 30 of the Top 50 All Time Box Office Grossing Movies were sequels, prequels, or spin-offs. That said only 2 of the Top 50 Best Reviewed Movies of All Time (according to Rotten Tomatoes adjusted scoring) were sequels.

You have standouts sequels that are often considered superior to the original films with the likes of Aliens, The Godfather: Part 2, Star Wars Episode V: The Empire Strikes Back, The Dark Knight, X-Men 2, The Road Warrior, and Star Trek II: The Wrath of Khan.

Then, on the opposite end of the spectrum, you have direct sequels to the original that are considered horrible by most with the likes of Highlander II: The Quickening, Speed 2: Cruise Control, Exorcist II: The Heretic, Grease 2, Caddyshack 2, and many more.

Next to those, you have later franchise sequels that didn’t live up to those that came before them with the likes of Indiana Jones and the Kingdom of the Crystal Skull, Batman and Robin, Spider-Man 3, A Good Day to Die Hard, Rocky V, and so many more.

And in the middle of all of those, you have sequels that are more of a mixed bag. Some love them. Some hate them. Some are indifferent. They often follow some of these below commandments, but not all of them.

So what makes a great sequel? Where do so many sequels go so wrong while so few manage to live up to expectations set forth by their predecessors?

As a confessed sequel-holic that would write any studio sequel in a heartbeat, I’ll attempt to explore the key directives to writing a great sequel.

Most screenwriters in Hollywood write on assignment. Within the studio system, when an original film does well — or, ironically enough, a sequel does well — it warrants another installment, because in the end, the studios need to make money, and what most people don’t understand is the real reason the studios develop so many sequels, prequels, remakes, or reboots is because that is what the audience often wants. We see the results of such time and time again. Last year, Jurassic World went on to become the third highest grossing film of all time and Star Wars: The Force Awakens blew away every major box office record and became the all-time grossing film in the history of cinema. Audiences love sequels, and thus, so do studios. They love something familiar. It gives them insurance for the multitude of money being spent at the theater on any given family or date outing.

All too often, original movies come and go with little to no audience — movies like Edge of Tomorrow that warrant big box office numbers with excellent casting, an excellent concept, and a great script to match it, under-perform. Why? Because audiences aren’t willing to take a chance — and perhaps some poor marketing in some cases.

That’s not to say that screenwriters and the powers that be shouldn’t create original films. They should. It’s just an explanation as to why studios feel the need to push sequels, prequels, remakes, and reboots — because the audience demands them.

So for screenwriters that really want to become professionals, one of the best things they can do is acclimate to the system and be ready to tackle any assignment that comes along if they’ve garnered some major attention from their writing. And hopefully such screenwriters can muster the success from such films and earn the freedom to pitch and write great original films. Such is this crazy business.

The Ten Commandments of Writing a Great Sequel

Note: We will forgo mention of sequels based on previously released source material — i.e. The Lord of the Rings, Harry Potter franchise, The Hunger Games franchise, etc. And also, BEWARE OF SPOILERS.

1. Thou Shall Ensure That the Original Warrants a Sequel

Okay, this primarily falls on the studio and producer, however, it’s one of the deciding factors of the eventual greatness — or lack thereof — of any given sequel.

Look no further than Highlander.

Highlander was an outstanding breakout genre film with the then unique premise of immortal warriors meeting across time to duel to the death by swords in a game where there can be only one. At the end of the film, the hero, Connor MacLeod of the Clan MacLeod, wins the final dual and receives the gift — whatever it may be. The signature tag line of the film is “there can be only one.” He’s the last immortal standing.

Due to the success of the film, the studio eventually wanted to capitalize, thus they greenlit Highlander II: The Quickening, a film that is virtually incoherent as a sequel. There have since been many follow-ups, all of which have been better than the second film in the franchise, however, all of which suffer the same fate. The original story never warranted a sequel.

Films like Steven Spielberg’s E.T. almost attained a sequel, obviously due to the success of the original. Thankfully, the director and studio were wise enough to put a halt to it. Why? Because the original didn’t warrant a sequel.

2. Thou Shall NOT Simply Remake the Original

Too many sequels suffer from this mistake. The Karate Kid franchise quickly tanked due to the regurgitation of the same premise. While the Rocky franchise managed to find its way around that problem well (see below), The Karate Kid films were weaker with each installment.

Chances are the original film was like most great films in the end — lightning in a bottle. A culmination of a great concept, a great script, a great cast, a great director, and debuting at a time when audiences were looking for something special. It’s very difficult to simply replicate that.

That said…

3. Thou Shall Understand That Audiences Want Something New, but the Same

Yes, this is where there exists that fine line between something new and something different. Screenwriters have to find a solid balance between the two.

The original was a success for a reason. Audiences responded to the concept, the characters, and the story. So what you have to do is to find the core of those elements and retain them.

Why do we watch Rocky movies? Well, we want to see Rocky as an underdog win the big fight. It’s no fun seeing him at the top of his game beating some schmuck, right? But how do you tell that same story over and over and not lose an audience, which is what the Rockyfranchise expertly managed to do from when it launched in 1976 and into the 1980s through its first four films (and then the sixth film in 2006 and the amazing Creed)?

It’s rather simple. You take the core of the original’s concept (underdog boxer), characters (Rocky, Adrian, Paulie, and Apollo), and story (struggling with the task of winning a seemingly unwinnable fight) and you give those elements new mass to tack onto that core. In the second film, it was about Rocky overcoming fame/infamy and actually winning the fight. In the third film, it was about succumbing to false success, getting soft, getting beaten, and making the comeback. In the fourth, it was about the purely impossible fight, but this time under the added guise of revenge.

Give audiences the familiar aspects of what they remember and then take the core of those very things and add additional mass to them with the likes of larger conflict, new character arcs, etc.

In the case of Creed, which is less of a sequel than a spin-off, we were given something new, yet the same because we had Rocky there training him.

4. Thou Shall NOT Dismiss What the Characters Accomplished in the Original

This is perhaps the worst offense of any sequel in my eyes — dismissing what the character(s) fought so hard to accomplish in the original or predecessor.

Look no further than the mixed bag that is Ghostbusters 2. While we have a strong element returning, as far as the chemistry of the characters (see below), where the film went wrong is having the characters back right where they started, or worse. In the end of the original Ghostbusters, Peter got the girl and the Ghostbusters were heralded as heroes, saving the great city of New York.

In the sequel, they’re right back where they started. Worse even. Peter and Dana aren’t together. The Ghostbusters aren’t only disbanded, they’re left shamed because of some negative fallout from their heroic efforts in the original. So not only is the sequel trying to remake the original, it’s jumped a few steps back after the leap forward that was the original.

That kills an audience. That breaks their heart. And they immediately disengage.

5. Thou Shall Take the Original Characters Forward

Ghostbusters 2 failed to do this.

On the other hand, look no further than Aliens, The Godfather: Part 2, Star Wars Episode V: The Empire Strikes Back, Star Wars Episode VI: The Return of the Jedi, The Road Warrior, Toy Story 2 and Toy Story 3, etc. These are all sequels that took their characters forward. Not only story-wise, but also their overall character arcs.

A franchise often lives and dies by its characters. There are exceptions in certain franchises, mostly horror properties like Paranormal Activity, Saw, etc. However, in most, audiences love the characters. And because of that, they want to see the characters move forward together.

Aliens moved the character of Ripley forward in such an amazing way and her character arc as a result of the events of the first film that she survived was outstanding. Enough to earn an Oscar nomination, mind you. Terminator 2: Judgement Day, which is also one of the greatest sequels of all time — standing next to the original, rather than above it — accomplishes this amazingly as well, as we see Sarah Connor’s character so drastically different as a result of what she survived.

Luke, Han, and Leia in the Star Wars original trilogy were always moving forward. Michael Corleone was always moving forward. Woody, Buzz, and their friends were always moving forward. This is what audiences crave. They want their characters to continue on in their journeys. Speaking of characters…

6. Thou Shall Remember That the Original Characters Are the Franchise

Look no further than the Fast and Furious franchise. If there is any example of the characters being the franchise, that’s it. The chemistry of the characters (RIP Paul Walker) is the true core of any franchise. The sequels where Paul Walker and Vin Diesel weren’t present and/or weren’t together were the films that didn’t do well at the box office. All too often, if you keep that and that alone, it can overcome otherwise lackluster villains and story lines in sequels.

The Lethal Weapon films thrived on this element. Audiences loved those characters. Riggs and Murtaugh, as well as the supporting characters of their family, friends, and loved ones, were the primary reason audiences kept coming back for more.

The worst thing that can happen to a sequel is to lose its original characters. This happens in Hollywood, due to contracts or actors not wanting to have another go around. Remember Speed 2: Cruise Control? It lost Keanu Reeves. ‘Nuff said.

Don’t forget the characters. Everything for a sequel starts with them and audiences will never forgive you and the powers that be if you lose their favorite characters.

7. Thou Shall Embrace the Mythos Created by the Original

Indiana Jones has his hat and his whip. Riggs has his martial arts and rage. Mad Max has his car (well, at least for the first two). Han Solo has the Millennium Falcon and Luke Skywalker has his X-Wing.

These are but just a few of the examples of mythos and overall atmosphere set by the original installment.

I was fortunate enough to pitch Rambo V to Millennium (the rights holder at the time), write the script (Rambo: Last Blood), and have the powers that be consider it. It was a dream come true. And you can bet that I had a reluctant warrior moment, a bow and arrow sequence, a knife, a cave, and many more subtle cues to the mythos of that franchise. That’s what makes a Rambo sequel feel like a Rambo film.

Embrace the mythos created before. Those character cues. An attitude. A history. A scar. A line. It wouldn’t be a Die Hard film if John McClane didn’t have a variation of “Yippee Ki Yay Motherf***er.”

That said, you can’t rely solely on those mythos either.

8. Thou Shall NOT Reinvent the Wheel

This thought might be attributed to some of the other points above, but we’re talking more about tone and genre. Highlander II: The Quickening turned the mysterious immortals into alien beings from another world. It was set in the future with a lot of future tech, while the original film was embedded in reality and the past with the low tech of swords. The sequel was suddenly a bad science fiction movie.

Gremlins 2: The New Batch turned into a neon-like black comedy while the original was actually a horror film with comedic elements to lighten the load and make it more accessible to the masses.

You want to offer something new with a sequel, but you can’t take it too far and make it into something the original never was.

9. Thou Shall Know That a Sequel Is Only as Good as Its Villain

Villains are key. A weak villain makes for weak conflict, which makes for a weak story that weakens the characters.

The Lethal Weapon franchise didn’t always have the greatest villains (with respect to Mr. Joshua), but the third film was the weakest in that respect by far, which made that film the weakest of the four.

Die Hard sequels could never top the original’s Hans Gruber (although the third film was smart enough to directly build off Hans).

The Dark Knight Rises was arguably overshadowed by the memory of Heath Ledger’s inimitable Joker.

The Karate Kid sequels never had their Johnny.

Rocky V’s antagonist couldn’t  stand up to Apollo Creed, Clubber Lang, or Ivan Drago.

Yet you look at the likes of amazing villains like Khan, the T-1000, the Alien Queen (and her kids), Heath Ledger’s amazing Joker, Boba Fett, and Wez and Lord Humungus (The Road Warrior) — all of them debuted in sequels.

The characters are only as strong as the ones they go up against.

10. Thou Shall Ask These Key Questions

What did they accomplish in the original or predecessor? What did they learn from that accomplishment? What conflict(s) can we throw at them to challenge the skills or knowledge that they had learned? How will they deal with that challenge and conflict? There’s the sequel…

Sequels should be a pleasure to write. Most of the time you’re working with characters that audiences already love. Most of the time you’re working with a core concept that audiences are already engaged by. There’s no need to re-introduce the characters or the concept in the opening pages because we have the original films for that. All screenwriters need to do is to take things forward, to embrace the core characters and concepts, throw more conflict at them, and take the audience on another great ride.