Brian Daboll is who we thought he was.
With a three back I formation and a shift, the Chiefs were able to get Jamaal Charles untouched up in to the Browns' secondary. With one good move by Charles and one whiff by TJ Ward, Charles was in the end zone.
What went wrong? Without being in D'Qwell Jackson's headset I can't know for sure, but it looked to me like the linebackers needed to shift once Kansas City motioned Bowe out into the slot. We may have had a blitz or some sort of stunt or slant by the line, but we needed to check out of it, shift our linebackers over, and play normal defense. Instead, Kansas City had us out-leveraged and they were able to outnumber us on half of the formation. Charles did the rest.
Thankfully, Daboll's opening drive success did not continue throughout the rest of the game. The Browns were able to stop the bleeding and rebound from allowing a big play.