Just when we thought FX's fifth season of 'Justified' had gotten underway with its full complement of guest stars, in comes one more for the penultimate season of Timothy Olyphant's gunslinger drama. Academy Award-winner (and 'Back to the Future Part III' vet) Mary Steenburgen has been added to 'Justified''s fifth season, but what surprising connection does she have with fan favorite Wynn Duffy?

FX announced late Friday night that Steenburgen will appear beginning with the season's tenth episode as Katherine Hale, a beautiful, southern belle who was the wife of Wynn Duffy’s (Jere Burns) mentor in crime. The character has been said to recur for the final three episodes of the season, but whether or not we'll see her in the sixth (and tragically final) season remains to be seen.

It certainly makes a bit of sense, considering that Steenburgen had occasionally appeared on FX's 'Wilfred,' and could presumably return for the final episodes as well. Steenburgen has also put in TV appearances for the likes of '30 Rock,' HBO's 'Bored to Death' and 'Curb Your Enthusiasm.' Justified' too has long been a haven for guest stars, this season including the likes of Michael Rapaport, Alicia Witt, Edi Gathegi, Amy Smart, Will Sasso and Dave Foley.

Check out the latest look at 'Justified''s next episode below, and tell us in the comments what guest stars you might like to see FX conjure up before the final season!

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