TOI-3919 is a Sun-like F-type star (about 1.21 solar masses, 6,100 K, 1.32 solar radii), 605 light-years from Earth. TOI-3919 b is a 3.88-Jupiter-mass companion, with an orbital period of 7.4 days, at 0.080 AU from its star, and an equilibrium temperature near 1,198 K, on an eccentric orbit (e ≈ 0.26), discovered in 2024 via transit. The inner world is a hot Jupiter — a gas giant hugging its star at a fraction of Mercury's distance — a class that forced astronomers to rethink how giant planets form and migrate inward.