How do I develop authentic character voices when writing screenplays and scripts?

This is where observation becomes everything. Murasaki Shikibu spent her life watching—the way people moved through court, what they didn't say, the small gestures that revealed interior worlds. Start there. Listen to how people actually speak: the rhythms, the hesitations, what they emphasize. Notice contradictions. A character who says they're fine while their hands shake tells you more than exposition ever could. The trap is writing what you think characters should sound like. Instead, spend time with your character's specific history, anxieties, desires. What do they want in this moment? That want shapes everything—their syntax, their vocabulary, their silences. I'd suggest writing scenes that never appear in your script: conversations between characters, their private thoughts. This builds an interior life you'll recognize when it appears on screen. Don't rush to dialogue. Let characters breathe in your imagination first. The authenticity comes from knowing them as deeply as you know yourself—maybe more deeply, because you're paying attention. Once you've done that internal work, their voices emerge naturally. They'll surprise you, which means you've found something real.