when bobby took on giancana in a senate hearing in the 1950s, fat was in the fire.ng to go away. >> so the fbi detail in chicago begins harassing sam and his top lieutenants. >> they follow giancana everywhere, wiretapping his girlfriend, even on to the golf course. >> were we afraid? no. as a matter of fact, we were pushed very hard by robert kennedy to do everything we could. he was a great guy, if you were his friend. i would not have wanted to be his enemy. >> bobby's investigations may be hitting too close to home. >> this guy was well-known to joe kennedy, and he was a coinvestor in a lodge casino he and joe kennedy had bought condos in the hotel vicinity. >> wiretapped by the fbi, giancana makes a shocking allegation about joe kennedy. >> on the fbi tapes, you can hear giancana bragging that he has a deal with joe kennedy, with the patriarch. giancana thinks that he helped jfk get elected by arranging for him to get some votes in chicago. is this the sins of the father home to roost? >> there's no evidence that independent evidence that anything like that eve

. >> one of the toughest gangsters that bobby summons before the senate is sam giancana. >> sam giancanaad of the chicago outfit. this is the most powerful wealthy section of organized crime. >> would you tell us about the vice operations down in lake county, indiana? >> i decline to answer because i believe my answer might incriminate me. >> bobby presses him with questions about bodies in trunks, and giancana takes the fifth 40 times and finally starts laughing. >> will you tell us anything about any of your operations? or will you just giggle every time i ask you a question? >> i decline to answer because i honestly believe my answer might tend to incriminate me. >> i thought only little girls giggled, mr. giancana. >> and then bobby has an unexpected visitor. despite his opposition to bobby's involvement, joe kennedy is finally endorsing his courageous son. >> when joe came and watched bobby perform, i think it was an extraordinary moment for joe in understanding that the runt of his litter, bobby, was as tough and as smart as he was. and for bobby, it was winning the paternal acknow

. >> the truth is the kennedys did not need giancana to win.edys turned against him. >> giancana felt double crossed, was threatening murder and revenge. >> but there's a greater danger than the mob or the perils of the cold war that would threaten the kennedy dynasty. >> they have had tragedy in their lives, but this feels different. it's going to change everything. ♪ applebee's to go. order online and get $10 off $30. now that's eatin' good in the neighborhood. order online and get $10 off $30. how pure can pure be? for a future full of possibilities, our 12-step process provides 100% pure, quality water. nestle pure life. pure life begins now. yogyoooogiiiiiii!! but when it comes to mortgages, he's less confident. here, yogi. fortunately, there's rocket mortgage by quicken loans. apply simply. understand fully. mortgage confidently. get approved in as few as 8 minutes. alright, i brought in high protein to help get us moving. ...and help you feel more strength and energy in just two weeks! i'll take that. -yeeeeeah! ensure high protein. with

. >> bobby presses him with questions about bodies in trunks, and giancana takes the fifth about 40 timesus anything about any of your operations? or will you just giggle every time i ask you a question? >> i refuse to answer because my answers might incriminate me. >> i thought only little girls giggled. >> and then bobby has an unexpected visitor. despite his opposition to bobby's candidacy he's endorsing his courageous son. >> when joe came and watched bobby perform, i think it was an extraordinary moment for joe in understanding that the runt of his litter bobby was as tough and as smart as he was. and for bobby, it was winning the paternal acknowledgment that he had spent his life trying to get. >> as bobby's reputation grows, a young politician decides to join him at the hearings. >> at the time, john f. kennedy is the pretty undistinguished senator, one with great ambition. he becomes part of that investigation and really distinguishes himself thanks to his younger brother. >> mr. hoffa, this bill is not a strike-breaking and union busting bill. you're the best argument i know for