After following a trail of clues that began with a cryptic E-mail, A tired middle-aged family man must enter a hidden world of supernatural mystery to save the soul of his childhood friend from an ancient secret society bent on hiding their existence at any cost.

I think Luke nailed it but here is another take. Here I wanted to suggest the focus be on why saving the childhood friend's soul is important to the present story, and the protag's family. The cryptic email is a nice plot point for the script but isn't "juicy" enough for a logline.

"A middle aged family man struggles to save the soul of his childhood friend before members of dark secret society come for his son."

That's a good re-write. I might change "as he tries to uncover" to "as he uncovers" (but that is just a tweak)

I like it!

Thanks guys!

I think Luke nailed it!