For last week's episode, What Hides Beneath, we looked at the infamous K-219 incident and wondered at the many mysteries of the vast ocean deep.
Some believe a strange underwater sound, known as a 'quacker,' may hold the key to unlocking the mystery.
However, in 1997 a sound known as the Bloop was picked up by hydrophones deep in the pacific ocean. The intriguing recording may yet prove to be the the most extraordinary underwater sound of them all…
Go to @unexplainedpod, facebook.com/unexplainedpodcast or unexplainedpodcast.com for more info. Thank you for listening.

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