For their upcoming mini-album release, the members of BTOB are not holding anything back - and the latest set of teaser images of the group really bares all.

The series of photos show BTOB sopping wet in the pouring rain.  The setup is simple, and the focus is clear - it's all about the muscles!

With the exception of Peniel and Sungjae, the rest of the BTOB member are flaunting their glistening abs.

Before the latest batch of photos, the group's agency, Cube Entertainment, had been teasing fans with audio teasers and details about the BTOB's new mini-album, which is scheduled for release on September 9.

The teaser for the title track, "Thriller," featured label-mates 4Minute and the track listing for the album has also been revealed, pumping fans up even further for the group's comeback.

Additionally, member Hyunsik will be showing off his composing talents for the first time with two different tracks on the new release, "Why" and "Star."

The music video for "Thriller" is set to be released on September 9, along with the group's third mini-album, but BTOB will be getting a jump start on promotions and plans to start performing their comeback stages on September 4.

If the new teaser images are any indication of what can be expected from BTOB next week - fans are in for a real treat.