Find a mysterious key

Michael feels unfulfilled in his life. His feelings of worthlessness and depression are alleviated when a crow bearing an enigmatic blue key in its claw gets struck by lightning and lands next to him. He had no companions with whom to spend time. It's a key that opens another gate and leads to something else. The way out of this gloomy and miserable world. Along the way, he makes new acquaintances, faces danger, and perhaps even falls in love for the first time.