In the quiet depths of a private lake, Marc Dupont, a former journalist passionate about history, discovers a fragment of an airplane bearing the mysterious symbol HST835. What starts as a simple curiosity quickly turns into a adventure thrilling, revealing secrets buried since the Cold War. With the help of Jean, an aviation expert, Marc embarks on a quest for truth that leads him from the depths of his lake to a secret site in the mountains. Each discovery brings more questions than answers, and soon, Marc finds himself at the heart of a story bigger than himself. Between duty of memory and protection of state secrets, 'Le Mystère du Lac HST835' is a history captivating discovery, mystery and a past that refuses to remain buried. Join Marc on his journey to unveil the truth hidden beneath the tranquil waters of his lake.”