Physicists Leonard and Sheldon understand everything from the inescapable gravitational pull of a black hole to the intricate structure of the atom. But take those atoms and assemble them into a woman, and their comprehension comes to a grinding halt. This season, Leonard gets a girl. So does Sheldon. (Sheldon?!), Howard drives the Mars Rover into a ditch, Raj woos a terminator, gorgeous girl-next-door Penny falls under the spell of Age of Conan, and super-smart, uberconfident Leslie Winkler reduces mere men to spineless jellyfish. Includes all 23 episodes, plus never-before-seen featurettes.

Title from container. Originally produced for broadcast in 2008-2009 season as 23 episodes of the television program: The Big Bang Theory. Special features: Physicist to the stars: real-life physicist/UCLA professor David Saltzberg's consulting relationship to the show; testing the infinite hilarity hypothesis in relation to the Big Bang Theory: season two's unique characters and characteristics; gag reel.

The bad fish paradigm -- The codpiece topology -- The barbarian sublimation -- The Griffin equivalency -- The Euclid alternative -- The Cooper-Nowitzki theorem -- The panty pinata polarization -- The lizard-Spock expansion -- The white asparagus triangulation -- The Vartabedian conundrum -- The bath item gift hypothesis -- The killer robot instability -- The friendship algorithm -- The financial permeability -- The maternal capacitance -- The cushion saturation -- The Terminator decoupling -- The work song nanocluster -- The dead hooker juxtaposition -- The Hofstadter isotope -- The Vegas renormalization -- The classified materials turbulence -- The monopolor expedition.