According to his co-star in The Jackal is Coming, Song Ji Hyo, Jaejoong only slept 30 minutes a day while filming K-Drama Time Slip Dr. Jin. The reason he supposedly slept so little was because he was filming The Jackal at the same time. Looking back, this would explain his less than lively appearance during Dr. Jin. Would you be able to function on 30 minutes of sleep? KrisE! @K_Kisses_KrisE