a "new york times" reporter decided to commision some tuna tests. a month later, the results found no tuna d.n.a. was present in the sample. ♪ ♪ ♪ >> at subway, there's been a lot of talk recently about whether or not subway tuna sandwiches contain any real tuna. well, after 55 years, it's finally time to come clean. here's the c.e.o. of subway, charles h. westin: >> subway tuna is made out of people! ( laughter ) >> okay, you got us. some of our sandwiches contain people. but for a limited time only, when you buy one foot-long man sandwich, you get another one for 50% off.that's a deal, regaf what the filling is made of. besides, human meat wouldn't be all that upsetting if you knew the recipe of our cheese sauce. so, come into subway today, and eat flesh. >> subway tuna is people! >> announcer: it's "the late show" with stephen colbert. tonight, block party. plus stephen welcomes christine baranski and musical guest joy oladokun. featuring jon batiste and stay human. and now, live on tape from the ed sullivan theater from new york city, it's steph