In this dissertation, I showed why it is difficult to discover grand corruption and make political and legal consequences. I examined five corruption investigation cases in South Korea that targeted the corrupt relationship between Geun-hye Park and the Choi family between the 1970s and 2017. From this study, I identified two unique ways corrupt actors protect the secrets of corruption. The first defensive mechanism is informational suppression that creates a structural barrier to the secrets of corruption. The other is political diversion that effectively obscures the discovered corruption through discursive tactics. Political diversion tactics obscure the meaning of the discovered corruption and redirect people's attention to an alternative issue. Lastly, I also identified three mechanisms that lead to anti-corruption outcomes. I propose a three-stage model to understand how anti-corruption actors overcome the influence of information suppression and political diversion and generate anti-corruption outcomes. In Stage 1, individual investigations are carried out by journalists or politicians (piecemeal revelations), however they are vulnerable to political spikes. In Stage 2, journalists and politicians begin a collaboration and create political pressure, and politicians bring media reports on the discovered corruption to the political process and generate political pressure on corrupt actors and their alliance. However, this collaboration makes the discovered corruption a highly politicized and polarized issue, so no consensus is made regarding how to address the discovered corruption. In Stage 3, social pressure from social movements strongly supports political pressure (Stage 2) and creates a legitimacy crisis. This loosens the networks of corrupt actors and their alliance, allowing anti-corruption actors to produce political and legal consequences.