Twilight and her friends enjoy a relaxing day at the beach, when Rainbow Dash has a startling encounter that leads to an exciting undersea adventure.

Featured on Equestria Daily on 09/28/2012

Pinkamena "Pinkie" Diane Pie is Us. In crazy brilliance, We made Pinkie so strange that We would never be suspected, and it worked until the very end. An end that came about, not because We failed, but because of inescapable circumstance.

Now, We must run.

We do not want to think about what they will do to Us if they catch Us.

From Twilight Sparkle's Secret Shipfic Folder
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K'larra was a deep cover changeling sent to spy on Ponyville in preparation for the invasion. Sazzix was a survivor of the invasion that slipped past the wards and posed as an ordinary pony.

They fell in love.

Then they figured out they were both changelings.

Then they got drunk.

After an accident, Rarity and Twilight are thrown in a race against time to stop their transformation into changelings before they become part of Chrysalis' swarm forever.