Dr. Erin Macdonald is an astrophysicist and science fiction consultant who advises major Hollywood productions on what they're screwing up in scripts. She joins Heaton to discuss the physics pitfalls science fiction constantly blunders into, from artificial gravity to the proliferation of cleavage in species that don't have mammalian glands. Plus: the difference between warp bubbles in Star Trek, the FTL drive in Battlestar Gallactica, and the hyperspace of Star Wars.