The central plot twist of My Hero Academia: Two Heroes is the revelation that the initial villain attack on I-Island was a ruse orchestrated by Professor David Shield and his assistant, Samuel Abraham. David's true intention was to create a crisis to bypass security and reclaim his greatest invention: a device capable of amplifying a person's Quirk exponentially. The device had been confiscated by sponsors due to its potential danger. David, horrified by the rapid decline of All Might's power, planned to use the device to restore his friend's abilities and preserve the Symbol of Peace.
However, this plan is hijacked by the supposedly fake villains, led by Wolfram, who is revealed to be a genuine, ruthless terrorist. Wolfram double-crosses David, steals the Quirk amplification device for himself, and decides to hold the island for a real ransom. The ultimate reveal comes during the final battle: Wolfram is not just a random villain but has been empowered by and is working with All For One, All Might's arch-nemesis. All For One secretly provided Wolfram with an additional Quirk and supported his plan in order to steal the amplification device and simultaneously crush All Might's spirit by turning his best friend's hope into a weapon of destruction. The film's climax sees a nearly depleted All Might and Deku (wearing Melissa's Full Gauntlet) combine their powers in a 'Double Detroit Smash' to defeat the super-powered Wolfram, destroying the device in the process and saving the island. In the aftermath, David, having seen Deku's heroic spirit, finally accepts that the future is safe in the hands of the next generation.