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The HBO series that Vincent Cassel appeared in during 2020 is Westworld, a science fiction Western television series created by Jonathan Nolan and Lisa Joy. The series is set in a futuristic Western-themed amusement park where guests can interact with lifelike android hosts. Cassel portrayed the character of Engerraund Serac, a wealthy investor and the co-founder of Serac , a leading technology company in the series.