Concise Investment Opportunity Memo?

Hello, fellow monkeys. 

I recently had an exciting investment opportunity reach my desk from an old friend out of undergrad. Without getting into too much detail, the opportunity is to invest in a new fund containing real and intellectual/operating assets in a niche market. My family office is a very old-school place, and our investments (which I underwrite and bring through closing) are almost exclusively brought in via the two Co-Presidents and their long (long) standing relationships. I've only even pitched a handful of deals to them, and the usual feedback is "we don't know these people" etc. etc.

However, this deal is potentially a once-in-a-lifetime type of investment, and I want to present it to them. The problem I'm facing is this. The deal materials are extensive, attractive, and compelling, but the chances of them looking at the executive overview or any other big decks are effectively zero. I want to pitch to them in person and hand them a one-page (max) memo or overview of the deal. If there's initial interest, I can give them my own detailed analysis and the investment materials, but if not at least I didn't oversell the deal.

There is so much information, though, and so many details that I'm absolutely struggling to get pen to paper on what needs to be included and what doesn't:

 Have you found a good way to essentially abstract a deal concisely and effectively into a one-page memo when it contains significant complexity? Where would I even start? Does anyone perhaps have an example of this or a short template that they might be willing to share?

Thanks in advance for your thoughts on this one. It's been a bit of a brain teaser. Writing up 5 pages would be easy, but something short enough for a quick glance but detailed enough to answer the obvious questions up front is trickier than I thought.