Misleading and unsubstantiated claims around the use of ballot drop boxes have a long history. Around the 2020 election we saw repeated claims related to “ballot harvesting,” suggesting that ballot boxes were being used to drop off large numbers of illegally gained ballots. Since the 2020 election, the unsubstantiated claim that people were hired to drop fake ballots in boxes in swing states during the U.S. 2020 election to prevent Donald Trump from winning has become a prominent online conspiracy theory. The narrative was popularized in Dinesh D'Souza’s film 2000 Mules released in May 2022. Coinciding with the film’s release, the claims presented in it gained traction among online discussions and a fraction of reactions centered on demands for ballot drop boxes to be banned. A small contingency of the film’s viewers proposed monitoring or observing ballot drop boxes in future elections, but those posts did not initially gain much traction. However, our analysis signals a behavioral shift, showing how conservative actors have exploited the film and its claims to motivate members of online audiences to monitor drop boxes.