r.j. anderson pull some mind-blowing moves. now we get to see what it took to pull these stunts off. new behind the scenes footage from tv underground. >> a guy tries to track down a girl he spotted in the grocery store. >> creepy. >> how social media just might help him score. >>> and -- [ shinning ] >> these sisters become an internet hit after using one beat. >> these girls are hot. >> meet the talented team in harmony. ♪ [ cheers ] >> several cities around the u.s. have proposed distracted walking laws. the video i am about to show you illustrates this. >> oh! thanks for the warning, baby. >> yeah. that's -- >> how does that happen? >> that person must have been listening to music with ear buds in their year. >> this woman was walking across the train tracks, with ear buds in, didn't see the lights, didn't pay attention to the guards coming down. and the train tried to slow down, but couldn't stop. it was already coming too fast. slams into her and drags her 50 feet. >> this is basically the definition of natural selection. i am not trying to be funny. i'm saying she is completel