American fans of 'Downton Abbey' (you know who you are) have had plenty to be frustrated about recently, what with series 3 not due to premiere in the U.S. until 2013, despite airing its post-series 3 Christmas special in the U.K. just yesterday. Prior to the special, rumors had swirled that longtime series star Dan Stevens would depart the series to pursue his theatre career, but is his exit set in stone? Find out about the big shocker for 'Downton Abbey' series 4!

American 'Downton Abbey' fans, ye be warned. Series 3 of the Julian Fellowes-created period drama won't begin airing until 2013, but this article contains major spoilers. As U.K. fans of the Emmy-winning series learned from last night's 'Downton Abbey' Christmas special, Dan Stevens' Matthew Crawley will be definitively absent beginnning with the fourth series.

We won't spill all the beans as to why it is that Crawley won't return, but actor Dan Stevens spoke about his confirmed departure with the U.K. Telegraph, calling it "a very difficult decision."

It felt like a good time to take stock, to take a moment. From a personal point of view, I wanted a chance to do other things. It is a very monopolising job. So there is a strange sense of liberation at the same time as great sadness because I am very, very fond of the show and always will be.

It was very emotional shooting the end of this series, because those guys are like family. We have been living together for three years and have been on the most amazing journey. I don’t think any of us, with the possible exception of Maggie, have had this kind of explosion in our career paths, and may never again. It has been so bizarre, and only those who have been through it can understand it.

Despite his departure, Stevens isn't exactly keeping a low profile, appearing currently appearing on Broadway with Jessica Chastain and David Strathairn in 'The Heiress.' Stevens claims his decision to leave 'Downton' had been made prior to shooting the third series, which premieres in the U.S. on January 6. The fourth series will begin shooting in early 2013, as well.

What say you, 'Downton' fans? Are you sad to see Dan Stevens leave behind Matthew Crawley? Check out the trailer for 'Downton Abbey' series 3 below and leave your thoughts in the comments!