Two years after M3GAN, a marvel of artificial intelligence, went rogue and embarked on a murderous rampage, its creator, Gemma, has become an advocate for government oversight of AI. Unbeknownst to her, a defense contractor has created a military-grade weapon known as Amelia, the ultimate infiltration spy. However, as Emlia's self-awareness increases, it becomes less interested in taking orders. Hoping to stop Emilia, Gemma decides to resurrect M3GAN, making it faster, stronger, and more lethal.