The official website for Kimetsu no Yaiba announced that the first five episodes of the TV series will receive a limited movie theater screening prior to TV broadcast. Titled Kimetsu no Yaiba: Kyoudai no Kizuna, it will center around the bond between the Kamado siblings and will premiere in Japanese theaters on March 29 for two weeks. A world premiere of the movie will be held on March 19 with Natsuki Hanae (Tanjirou Kamado) and Akari Kito (Nezuko Kamado) appearing for a talk show.
The manga is serialized via Weekly Shounen Jump magazine and 14 compiled volumes have been released as of January 9. The TV anime is scheduled for this spring.
Note: The video is region-locked; click here for an alternative link.