Just got my copy of Genesys and am exited to start creating my own scenarios and adventures. My first attempt is an original mystery centered around Agatha Christie's Belgian detective, Hercule Poirot. It's a snowbound whodunit over the Christmas holidays with the classic Poirot showdown at the finale. I'm having fun plotting the mystery and developing clues for the characters to discover.

However, I am new to Genesys and RPGs in general. I am an author, so the story narrative feels fun and natural. Yet, some of the mechanics of being GM and managing stats and encounters are new to me. Does anyone have any pointers or suggestions as to how I could develop a really engaging adventure for me and my pals?

Thanks!

I would just say prepare to ad lib. Players will always go their own way; it’d be best if you can adapt with the flow. Hopefully you can get your plot in with a few ad hoc tweaks.

Your concept sounds fun. Seems like you'll be focused on social encounters, and Genesys has a chapter devoted to them (chapter 7, pg 118). Also, character motivations will be important, both for your players and for the NPCs you'll be creating (step six of character creation, pg 46).

Investigation/mystery stories can be a challenge to run, but quite satisfying for the players when they put the pieces together. Remember to let the players fail forward. If they can't uncover a clue or get info out of an NPC by succeeding on a skill check, find a way to turn that poor result into a backhanded win.

Improvisation is key. Create your NPCs and setpieces and make a list of your clues, but be ready to let the players navigate their own path through your plot. They will surprise you with what they invent, and even more by what they miss. But, the game is a collaborative effort. Be ready to let the story be one you and players create together.

I'd recommend this great essay by Justin Alexander on the subject of running mystery rpgs. It helped me a lot as I prepared my first who-done-it.