By Fernanda Rossi
Q: Should my trailer reveal the entire narrative arc of the story (where it's headed) or focus only on the premise and characters?
Fernanda: The eternal dilemma of how much is too much and how little is too little. You're spot on that you need to make sure the narrative arc is explicit, yet not fully developed till the end. Because if funders get closure and they feel it works as a nice tidy short film, why would they give you money for a longer piece? They'll pat you on the back, thank you for sharing and wish you good luck.
Definitely introduce the premise right from the start as well as the characters or host/narrator, the character's goals and some obstacles if any. As far as cliffhangers go, there are three techniques I found that work well to create some suspense: aposiopesis (literary term that means "unfinished action"), purpose (when the character establish an intention) and questioning (narrator or character question the very premise or status quo). I'll discuss four opening techniques at the workshop. For now I hope this tips walk you through the bare essentials!
About Fernanda Rossi: Internationally renowned speaker and story consultant Fernanda Rossi has doctored over 300 films, including Academy Award nominees(R) The Garden, by Scott Hamilton Kennedy, and Recycled Life, by Leslie Iwerks; as well as hundreds of trailers, many of which received funding from ITVS, NYSCA and NFB. She is the author of the book that, according to industry professionals is the bible on demo production: Trailer Mechanics: A Guide to Making your Documentary Fundraising Demo.