During their hiatus, Mayday released the autobiographical documentary titled The Wings of Dream <<Yao Gun Ben Shi >> , with ticket sales hitting more than NT1.2 million in barely three days. They also released an accompanying soundtrack.  After Masa's official release from the military, the band regrouped and made a return to the music industry. To mark the event, Mayday held their City of the Sky <<Tian Kong Zhi Cheng >>  concert on 16 August 2004 at the Taipei Municipal Stadium. The concert attracted nearly 40,000 fans, which broke the record for the most concert-goers in Taiwan, a record previously held by Michael Jackson.  On 11 November 2003, the band also released their 4th studio album Time Machine <<Shi Guang Ji >> . Sales of the album hit more than 15,000 within two days, with Mayday seeing no decline in their popularity despite their hiatus. Time Machine also won Mayday their second Best Musical Group award at the 15th Golden Melody Awards.  In the summer of 2004, Mayday also participated in the making of the soundtrack for the movie Love of May, in which they also presented new arrangements of some of their old songs. Stone also had a supporting role in the movie.  5 November 2004 saw the release of their critically acclaimed 5th studio album God's Children Are All Dancing/Flying Angels With A Falling Soul <<Shen De Hai Zi Du Zai Tiao Wu >> . This album used the simultaneous recording technique to create the distinctive "band" sound of their past albums and was specially recorded at Lake Kawaguchi, Japan. In 2005, they also released a best of compilation album Just My Pride <<Zhi Zu  Zui Zhen Jie Zuo Xuan >> , which included six new songs and favourites culled from previous albums.

Answer this question "What happened with the return to the music scene in 2004?" by extracting the answer from the text above.
To mark the event, Mayday held their City of the Sky <<Tian Kong Zhi Cheng >>  concert on 16 August 2004 at the Taipei Municipal Stadium.