The official Poldark account tweeted a photo of the actor and captioned it, "More #Poldark S4 casting news: the wonderful Max Bennett has been cast as the... Less than wonderful Monk Adderley!"
According to a BBC synopsis, Monk Adderley is "an unscrupulous society figure who is on a collision course with the Poldarks".
The casting follows news that series four will introduce a "powerful" new character in Lady Whitworth, who is the mother of Reverend Osborne.
Lady Whitworth will be played by Rebecca Front.
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