Opening on a wide 379 screens, The Magic Hour amassed $4.81m (Y506m) on 370,000 admissions, for a strong per screen average of $12,684.
The film stars Koichi Sato (Sukiyaki Western: Django), Satoshi Tsumabuki (Dororo), Eri Fukatsu, Haruka Ayase and Toshiyuki Nishida.
Tsumabuki plays a low-level gangster who is ordered to find a legendary hit man within five days, or face death for having an affair with a mobster's mistress. He hires an out-of-work actor (Sato) to play the part, convincing him it's for a movie role.
Mitani wrote and directed 2006's hotel ensemble comedy Suite Dreams, which also featured Sato and Nishida. Suite Dreams earned $57.8m (Y6.08b) at the box office, going on to become the most successful comedy in Japanese history.
Distributor Toho expects The Magic Hour to exceed the Suite Dreams box office take.
The Magic Hour beat out two other new releases from major studios Shochiku and Toei. Shochiku's fish market comedy drama The Taste Of Fish, competing at the Shanghai film festival next week, landed in sixth place. Toei's teen sci-fi film God's Puzzle from Takashi Miike was nowhere in the top ten despite major promotion.
The weekend's top ten according to admissions are as follows. The full chart with gross figures will be available tomorrow (June 10) in Screendaily.com's Global Box Office section.
1. The Magic Hour (Japan) Toho
2. The Chronicles Of Narnia: Prince Caspian (US) Walt Disney Studios Motion Pictures International
3. Partners, The Movie (Japan) Toei
4. Cyborg She (Japan) Gaga
5. Rambo (US) Gaga
6. The Taste Of Fish (Japan) Shochiku
7. 21 (US) Sony Pictures Releasing International
8. The Bucket List (US) Warner Brothers
9. After School (Japan) KlockWorx
10. 27 Dresses (US) 20th Century Fox