This article analyses the challenges faced by the #MeToo campaign, during its first weeks of existence on Twitter. These included the challenges of maintaining its frame, and making a consistent impact in a complex and volatile media landscape. This mixed-methods study draws on a data set of four million tweets accessed through Twitter's public data interface. It addresses the following research questions: To what degree did the #MeToo campaign on Twitter have a clear focus, and was it able to maintain it? How did the tone of the campaign on Twitter change over time, in terms of the positivity or negativity of expressed sentiments? To what extent were tweets simply reiterated, or instead made the subject of customization and active debate? The article finds that #MeToo quickly started to lose its momentum after the initial and explosive impact, with noise, antagonism, and sloganization increasingly weighing down and diluting the campaign. However, a cross-platform perspective is needed to grasp a full picture of how hashtag activism functions; including the #MeToo campaign.