Because cinematics are, in effect, short films, every single technique that factors into writing great films also applies to cinematics. This includes creating unique characters, riveting dialogue, compelling scenes, and so on.
Poorly written cinematics can be:
Here are a few guidelines for writing riveting cinematics.
Few or No "Blocks"
When one is writing in screenplay format, with the dialogue in a column in the middle of the page, I call a block any time there are three or more lines (not sentences) in a character's dialogue. Minimize these blocks or your characters will sound like they're making speeches, not conversing. An exception might be in a formal or informal debate.
Give Major Characters Interesting Diamonds
Characters should possess a colorful grouping of personality Traits that determine their dialogue and their actions (a Character Diamond). To learn about creating colorful Character Diamonds, see Chapter 2.1, "NPC Interesting Techniques."
Ambivalence Between Characters Can Make a Cinematic More Interesting
It's okay, in a cinematic, for a character to have mixed feelings about another character. For instance, a character could feel, simultaneously, both appreciation and annoyance toward a second character.
Or, instead of simple ambivalence, you can make the relationships between characters even more complex with this next technique:
Use Layer Cakes Between Characters to Give Their Relationships Complexity Beyond Simple Ambivalence
Layer Cakes mean that Character A has various layers of feelings toward Character B. These varied feelings can present themselves either simultaneously or sequentially. For a full description of how to create Layer Cakes, take a look at Chapter 2.8, "NPC Toward NPC Relationship Deepening Techniques."
Watch Out for the Clichè and Bland Lines
"You won't get away with this!" is clichè and bland. "How's it going?" is bland. Such lines are fine for the first draft or two. But try to avoid any such lines in a cinematic.
Can It Be Said or Told Better with Actions Rather Than Words?
This one in particular will become more and more important as our ability to animate facial expressions in games improves.
Time Permitting, It's Okay to Briefly Stray from the Topic at Hand
Conversations rarely stick to a single topic. Instead, they tend to weave in other strands, some of which never go anywhere. However, with cinematics currently being so expensive to produce and players' eagerness to get on to gameplaying always present, your cinematics might not be able to benefit from this writing technique.
Either have the player be unable to predict the outcome of the cinematic, or else be unable predict the way that outcome is achieved.
Obstacles and Interruptions Can Make a Cinematic More Interesting
This is especially true if the obstacle or interruption comes at a seemingly inappropriate time, such as when two people are arguing.
Use Dialogue Devices to Make the Dialogue Sound Natural
There are many techniques you can employ to make dialogue capture the natural sound of spoken speech. I call these Dialogue Devices. Many are used and explained in the example that follows.
The previous sections explain a few techniques you can use to make your cinematics more interesting. They're easier to understand if you see them applied in an example, so let's look at one.