Gatsby style surprise murder mystery party, any ideas?

I'm planning my birthday party. I have 8 friends coming over, and I have access to a big fancy lodge to host at. all I've told them so far is that everyone is dressing up for a nice dinner, and I plan to be "murdered" during my toast after dinner, (lights go out, sprawled on table, knife in back, etc) and from there have "letters" handed out containing rules and characters for everyone. Is this style of surprise murder mystery feasible? or do I need to warn everyone first. Our group is all theater/acting nerds so I don't doubt they could go along with it, and I'm planning on basing the characters heavily on the actual people. I'm now stuck on making the clues/puzzles and need help figuring out how to organize the thing. I've put together motives for everyone and an outline of the night, but I'm stuck on how much of it should be physically looking around the property for clues, like a scavenger hunt? or should it be more typical and social based. This is my first time hosting an event like this so any advice is much appreciated, thanks! :)