At the start of 2014, we cut over 2000+ people at American Express from waterfall to a full agile concept and delivery life cycle. Confidence was high despite the risk. A year of diligent preparation had put all the textbook conditions for success in place: senior leadership was on board; employees were psyched; we had coaches on the ground; a well thought-out agile Software Development Life Cycle; and a continuous integration and delivery infrastructure ready to go. Expectations were managed for the whole organization that the first few sprints for the 40+ scrum teams would be turbulent. Then Sprint Three happened. A revolt erupted across our teams that threatened the whole transformation. The window of opportunity to get it back on track was dwindling. This talk lays out what happened, the five-WHYs behind it, the resolution, and what others can learn from our experience when embarking on a large scale transformation.