Train collision in N.D.. Oil tank cars caught fire …. Obviously the death of Matthew Crawley (Dan Stevens) in a car crash at the end of season three has the greatest impact on his wife, now widow, Lady Mary. She had … It appears there has been an effort to soften Mrs. Hughes as a contrast to Carson, and they are an amusing odd couple at times. … It's strange when you consider that the worlds of Downton Abbey and Boardwalk Empire essentially exist simultaneously. …

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Downton Abbey has character – lots of them – in season four …