Considering we're almost half-way through the show's eighth season, with no signs of stopping, those wacky 'Supernatural' Winchesters have just about done it all. Everything from taking on bank robbers cartoon style, to traveling back and time to meet their own mother, nothing is off limits for Sam and Dean. So what's the big to do about upcoming episode "As Time Goes By," and what does an important new character played by 'ER' vet Gil McKinney have to do with it? Who might he be to Sam and Dean?

A few weeks back we'd heard that 'Supernatural' was to dip into its well of time-travel tales once more with "As Time Goes By," this time bringing a mysterious man to the future, said to be a “Robert Downey Jr. meets Cary Grant” type who joins a 1958 demon cult in the interest of protecting his young son. We sure hope he succeeds, as The Huffington Post has revealed that the man is none other than Henry Winchester, Sam and Dean's paternal grandfather!

With the character to be played by 'ER' and 'Friday Night Lights' vet Gil McKinney, and followed to the future by followed by a “sexy, strong Katharine Hepburn type” named Josie Sands, 'Supernatural' star Jensen Ackles spoke a bit about the character's inclusion:

This is a [man] we knew nothing about, because he was never involved in our lives or the lives of people that were involved directly with us.  It’s kind of getting some insight into the life and the legacy of the Winchesters, which is something that we as characters never really knew.

Ackles' co-star Jared Padalecki also noted how the show had previously shown the extended family on their mother side, the Campbells, but "As Time Goes By" allowed them to flesh out the Winchester side of things a bit.

What say you?  Are you excited to meet Sam and Dean's other grandpa? Give us your 'Supernatural' predictions for "As Time Goes By" in the comments!

More From ScreenCrush