Adam Levine -- Total White Out! Moment of Impact in Sugar Bombing (VIDEO)

Adam Levine never had a chance against the sugar bomber outside Jimmy Kimmel's studio Wednesday evening ... and that's evident in this new angle of the attack.

You can see Adam was laser focused at the time ... on signing autographs for the mob of fans gathered to see him -- and the attacker totally blended into the crowd.

Watch the video ... two things are amazing here: 1. Adam is pissed, but is still remarkably calm -- and 2. Maroon 5 fans are rabid.

You gotta see and hear them go berserk. Those young girls kiss their mother's with those mouths?