Sakanaction's new single "Goodbye / Eureka" will be released on January 15, 2014. 

The band's 9th single will be released in both limited (CD+DVD) and regular (CD-only) editions. "Goodbye" is a new song that's currently being recorded, and "Eureka" was picked up as the ending theme for the movie 'Judge!'.

More details will be revealed at a later date. 

Source: natalie