It's time for a good old-fashioned Supernatural flashback.

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Sam (Jared Padalecki) and Dean (Jensen Ackles) will dive into the world of imaginary friends during "Just My Imagination," and the episode will involve a flashback to young Sammy. Directed by Supernatural alum Richard Speight, Jr., the December installment will debut the newest iteration of Jared Padalecki's character.

Previously portrayed by the now grownup Colin Ford, the role of little Sam Winchester will now be played by Dylan Kingwell.

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"Sam is shocked when his childhood imaginary friend Sully (guest star Nate Torrence) makes an unexpected appearance," The CW teased. "Sam can't understand why he'd see Sully now but what's even more surprising is that Dean can see him, too. Flashbacks reveal young Sam's friendship with Sully and why he needed him."

Well, we can think of a host of reasons a lonely Sam might need an imaginary friend. A lonely and frightening childhood comes to mind. Tell us your theories in the comments below!

Supernatural airs Wednesdays at 9 p.m. ET on The CW.