Big Guy and Rusty the Boy Robot

Sibling Mine (2x8)

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When Quark's Dr. Kirby disappears after an experiment with his Quantum Machine goes awry, a hostile monster emerges and goes on a rampage, apparently having destroyed the doctor. Back at Quark, Rusty discovers a previous ""boy robot"" prototype. Hoping for a new friend, Rusty reassembles the robot, who he names ""Earl."" But Earl's relentlessly aggressive programming turns him against the heroes.