However, they\u2019re not the only major cast members this time around \u2013 two major guest stars are joining, with Katherine Waterston playing MI5 agent Alison Dunn and \u1e62\u1ecdp\u1eb9\u0301 D\u00ecr\u00eds\u00f9 playing Sean Donovan, the former head of security at the British embassy in Istanbul.<\/p>\n
RadioTimes.com<\/a> caught up with the show\u2019s creator Will Smith to talk about the new season, and he explained why D\u00ecr\u00eds\u00f9 was so perfect as Sean, who is a man on a very specific mission this season, and what he brought to the role.<\/p>\n Smith explained: \u201cHe\u2019s fantastic at action, but he\u2019s also a brilliant actor. What we wanted for that part, the Sean Donovan part, is you\u2019ve got to believe his anguish and his grief and that that is motivating him. If you don\u2019t believe that, I don\u2019t think you buy all things he does, and you start to question it.<\/p>\n \u201cHe just brought a reality to it, and an emotional heart and heft that just brings the central plot alive, brings it all alive. He\u2019s phenomenal and I loved working with \u1e62\u1ecdp\u1eb9\u0301. He\u2019s already a massive star and he\u2019s gonna be an even bigger star. I mean, he\u2019s off, he\u2019s away.\u201d<\/p>\n The official synopsis for this third season says: \u201cA romantic liaison in Istanbul threatens to expose a buried MI5 secret in London.<\/p>\n \u201cWhen Jackson Lamb and his team of misfits are dragged into the fight, they find themselves caught in a conspiracy that threatens the future not just of Slough House but of MI5 itself.\u201d<\/p>\n Read more:<\/strong><\/p>\n A fourth season of Slow Horses<\/a> has already been confirmed, which will be based on Mick Herron\u2019s novel Spook Street and will feature\u00a0Hugo Weaving and Joanna Scanlan<\/a> in its guest cast.<\/p> ![\"Saskia](\"https:\/\/images.immediate.co.uk\/production\/volatile\/sites\/3\/2023\/09\/SlowHorsesS302-1567ada.jpg?quality=90&resize=619%2C413\" "\\"Slow")
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