Lee is now touring and will reach Beijing on Nov 16. Called As Youth Cannot Stay, the tour will cover Lee's music career from 1984, and he will perform songs from his own albums and songs he wrote for other singers.

Tickets for his Beijing concert sold out in less than 72 hours.

Maintaining a low profile, Lee declined all interview requests and did not give press conferences before the concerts.

However, in a media release from his record company, Lee speaks at length about his motivations and feelings on returning to the spotlight.

A 30-year veteran of the music industry and one of the most successful hit-maker producers behind many singers across Hong Kong, Taiwan and the mainland, including his ex-wife Sandy Lam, Lee had withdrawn from the limelight to focus on making stringed instruments, with his own guitar brand, Lee Guitars, he founded in 2002.

The music video to Hills shows his guitar making process and the handwritten draft of the song, it is simple yet touching.

He sings: "I still have much to say so I collect my words and write the song."

According to Lee, the melody of Hills was finished 10 years ago but the lyrics were written just two months before it was released.

"It's a song about my life experience. Some people feel it's sad but I don't think so. It's about a middle-aged man, looking back on his life with a little bit of humor and nostalgia," Lee says.