If you see a bunch of little green men running around Burien on Friday, Aug. 4, there's no need to grab the aluminum foil — it's just the Burien UFO festival (BUFO).

The annual event, hosted this year at the Heritage Highline Museum, brings believers and non-believers alike together for presentations, a costume contest, and live music.

Regardless of how seriously you take the concept of aliens running around our planet — it seems that the US Congress is on the case — the fest honors a real event (or at least the real investigation of a claim). It's where we even got the term "flying saucer."

What's that in the sky?

BUFO was first launched by John White, the executive producer of "The Maury Island Incident" short film named after a mysterious event from 76 years ago.

On June 21,1947 (two weeks before Roswell), Harold Dahl, his son, and their dog took their boat out to tour the Puget Sound. During their ride, Dahl said six "flying saucers" appeared in the sky above his boat. One of the aircraft seemed off-kilter and allegedly exploded, dumping a "material resembling lava rocks" onto the boat. The debris broke Dahl's arm and killed the dog.

Dahl reported the event to his supervisor and claimed he was then visited by a "man in black" (yes, like the Will Smith character). The person supposedly told Dahl to stop talking about the UFOs and threatened that "bad things will happen" if he didn't shut up.

No, but what was it? Really.

The case was then investigated by the FBI, who declared the event a hoax. But a recording showed Dahl was potentially freaked out by the investigation, which may have influenced his testimony. So perhaps the verdict is still out.

Today's festival will actually have presenters who claim to have evidence from the event, so maybe you should grab that tinfoil after all.