The Challenge (1998)

S6E6 The Fogman

Cyril, known as the fogman, is well-liked by the engines for his crucial role in placing detonators that alert them to foggy conditions. However, the Fat Controller opts to replace him with a noisy foghorn. Unfortunately, this loud device triggers a rockslide that ultimately destroys it, just as Thomas approaches down the track. The incident highlights the importance of Cyril's work and the dangers of relying solely on technology in challenging weather conditions.