Are you caught up with everything up until the most recent fragment? If not, I highly suggest reading through the Basecamp Blog - that'll get you up to speed on the first three fragments.
If you're already caught up on the stuff that's happened up until fragment four, then here's the gist of the latest fragment. From King Rabbit's fragment, we found a link on the Those Who Did Not Die page. The link led to a website called the Forest of Darkening Glass and was set up by Susan Lachmann, the mother of a boy named Brandon who died in 1986. The website has changed since then, but you can see the original here. As we explored the website, we found that it was being altered by a group called The Devoted. They came in contact with us, seeming to want help in contacting Brandon, who they believe had not died. They thought he had left this world for somewhere better - somewhere where magic exists.
We started with what the Devoted called the first trial, which had four beacons. Basically, the Devoted gave us a bunch of files, documents that Brandon himself had created for an RPG game. We had to use the files to solve the beacons and then send the information to the Devoted once we were done. You can read what we did over on the Fragment Four category, here's the links to beacons one, two, three, and four. The gist of this - each of those beacons led to a location in New York City. Using all four locations in an x-marks-the-spot manner, we were able to find another real life location, the Triplets Bridge in Central Park. We had a mountaineer go there in real life, where they found a disk. The disk led to new documents from the Devoted and we were onto the second trial.
The second trial is a little more complicated. Using the numbers on the disk, we found new pages on the Forest of Darkening Glass website - more files from Brandon. To sum it up, the puzzles we solved led us to the Met Museum's Cloisters, where we found the next disk and another hint from Brandon. Except...here's where things get a bit complicated - someone from the Devoted helped us out and they weren't supposed to. They found out and...now they're angry at us. We're not in contact with them anymore.
So, long story short, we're now on what you would call the third trial, I guess. Trying to figure out where to go next and what we can do to help Brandon and open the Book of Briar's next lock. Hopefully that helps you get caught up!