His family was Republican during the Spanish Civil War, ironic as he
played the pro-Franco, fascist Captain Vidal in Pan's Labyrinth.
He is fluent in Spanish, French, English and his native Catalan.
When he was cast in Pan's Labyrinth (2006) to play Captain Vidal, the producers tried to convince director Guillermo del Toro that he may not be right for the part, as he was considered a comedic actor at the time. Del Toro disagreed and kept him in the film. López' portrayal was later praised by fans of the film and critics alike.
Has a paper written on his work and Spanish stereotypes, titled "Why
Spaniards make good bad guys: Sergi Lopez and the Persistence of the
Black Legend in contemporary European cinema" by Professor Samuel
Amago.