âHappiness is the enemy,â says Niki Lauda (Daniel BrĂŒhl) during Rush (15A), and you fear that Ron Howardâs movie about the rivalry between 1970s Formula 1 stars Lauda and James Hunt (Chris Hemsworth) is going to descend into simplistic tale of Huntâs cavalier flair triumphing over Laudaâs dour efficiency.