A new trailer for Slow Horses has given fans a glimpse of Gary Oldman and his dysfunctional team of British intelligence agents in series four. The teaser of the hit drama, which is based on Mick Herron's Slough House novels, follows the agents as they are involved in a case about an explosion in central London. Returning cast members including Jack Lowden , Kristin Scott Thomas , and Rosalind Eleazar join newcomers Hugo Weaving, James Callis, Ruth Bradley, Joanna Scanlan, and Tom Brooke.
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