Renny Harlin recounted the glasses debate he had with Val Kilmer during the filming of 'Mindhunters'. During a masterclass at the Mediterranean Film Festival in Malta, Harlin emphasized that the most important rule for winning over actors on set is preparation. The seasoned director shared experiences he gained while working with major stars like Bruce Willis, Samuel L. Jackson, and Sylvester Stallone over his career spanning more than 50 years.

Harlin noted that preparation is not just limited to scripts and storyboards, but also includes learning the challenging scenes required by his films. For example, he mentioned that he learned about mountaineering for 'Cliffhanger', gathered information about airplanes for 'Die Hard 2', and even learned how to operate a helicopter. This preparation process helps him build trust with the actors and earns their confidence by providing clear information on technical matters.

In an anecdote about Kilmer, Harlin shared that Kilmer expressed a desire to wear glasses to fit his character. Harlin pointed out that Kilmer had been without glasses in previously filmed scenes, indicating that this would create continuity issues. However, Kilmer argued that his character had a more industrious nature and decided to wear glasses. This led to a debate that affected the dynamics on set, and Harlin highlighted that such situations could increase the challenges of directing.

In conclusion, Harlin's experience showcased how complex actor management can be and reiterated the importance of preparation. Both Harlin and Kilmer respected each other during this process, striving to find a creative solution.