HBO fantasy drama 'Game of Thrones' is no stranger to cast changes between seasons, but a season 5 role will have a darker cloud over it, as we've learned that 86 year-old Irish actor J.J. Murphy has sadly died. The 'Dracula Untold' star was set to appear in 'Game of Thrones' season 5 in the role of eldest Night's Watch member Ser Denys Mallister, and had completed the first day of filming before his death.

The Belfast Telegraph reports that the actor collapsed and died on Friday, just four days after shooting his first season 5 scenes, though no cause of death has been obtained just yet. HBO and 'Game of Thrones' showrunners David Benioff and Dan Weiss offered the following statement on Murphy's passing, also clarifying the death's impact on production:

We will not be recasting J.J. Murphy. He was a lovely man, and the best Denys Mallister we could have hoped for. And now his watch is ended.

While we wait for ‘Game of Thrones’ season 5, we at least know of a multitude of other new characters cast, including those that confirm we’ll be visiting the oft-mentioned kingdom of Dorne, for which Spain location shoots will double. We’ll also meet fewer new characters in season 5 than in prior years, as the next cycle will prove to be something of a midpoint for the series’ run. As expected, the story will draw heavily from George R.R. Martin‘s fourth and fifth novels, ‘A Feast for Crows’ and ‘A Dance with Dragons,' while HBO has also provided a list of directors.

Considering that neither Murphy nor his character were included in the Comic-Con 2014 video that showed off the 'Game of Thrones' cast's season 5 additions, it remains to be seen how the series will write out Ser Denys Mallister, even as a relatively minor role. We've included the new cast video below, and mourn J.J. Murphy's loss in the meantime.

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