03/08/2013 09:27 am ET

Siobhan Finneran Opens Up About 'Downton Abbey' Departure

O'Brien (Siobhan Finneran) will no longer be terrorizing Downton with her conniving ways, and no one is more relieved than Finneran herself.

In an interview with the Daily Mail, the actress went into greater detail about why she left "Downton Abbey," which she announced her departure from earlier this month.

"I signed up to do three series and that was all I wanted to do," she explained. "I had great fun doing it but I just didn’t want to do it any more. I decided this before we even did the last series. When I stop loving something, I stop doing it."

But after Dan Stevens' dramatic car accident
at the end of Season 3, Finneran is wary of what series creator Julian Fellowes will write for O'Brien.

"I have no idea how they will explain my absence," she laughed.

She may have run out of "Downton" steam, but Finneran had a blast while it lasted.

"O'Brien is a thoroughly despicable human being -- that was great to play," she told the Press Association, via HuffPost UK.

Season 4 of "Downton Abbey" will air in January 2014.

"Downton Abbey"