During the filming of *Men in Black*, Tommy Lee Jones repeatedly tried to add comedy to his performance, but director Barry Sonnenfeld insisted that Agent K remain completely serious and expressionless. Jones reportedly resented being treated as the humourless counterpart to Will Smith and froze Sonnenfeld out for around 20 weeks, creating tension during the production.

Sonnenfeld later recalled that Jones’s agent complained that the director wanted only Smith to be funny, although Sonnenfeld believed Jones would ultimately be funnier. The director’s approach proved effective: Jones’s deadpan performance created a strong contrast with Smith’s energetic Agent J, making Jones an important source of the film’s humour despite his character’s seriousness.