The Changelings are back for Star Trek: Picard season 3 and something is even more amiss than we thought...

Screen Rant's exclusive clip for episode 5 of the hit show - and one of the best seasons of Star Trek ever - offers a major reveal that highlights just how vulnerable Starfleet really is.

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Behind the mystery of their intentions may be the mystery of what's happening to the changelings themselves, as episodes 4 and 5 tease the curiously changing physiology of the beings introduced, or shall way say, liquefied so far. But there's something else too as we dig into the epidermis of Changling. Watch our Picard clip below:

The clip shows Ensign Sidney La Forge (Ashlei Sharpe Chestnut), daughter of Geordi La Forge (LeVar Burton), reacting to seeing her dead Doppelganger (thanks to a phaser blast from Seven in episode 4), and through the analysis by Beverly Crusher (Gates McFadden) and Dr. Ohk (Tiffany Shepis), we learn that the Changelings can now pass traditional blood screening tests. Changelings can now, and have been able to for some time, bypass Star Trek security.

The threat to Starfleet is worse than we knew. Stay tuned for more!

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Star Trek: Picard Season 3 streams Thursdays on Paramount+.