one of the fbi's most wanted. >> cunanan that summer was america's terrorist. >> cunanan. >> cunanan. >> andrew cunanan. >> he had people in a panic. >> the serial killer's still out on the loose. i mean, that scares me still. >> eyewitnesses say the killer walked up, shot versace twice in the back of the head, and ran. >> oh, my god, there is blood everywhere. please help me! please! >> a fashion icon gunned down outside his house, execution-style in broad daylight, it is so brazen. >> the fbi says cunanan is on a killing spree. >> has involved five victims in four states. >> nobody knew where he was going to strike next. nobody knew what was motivating him. >> 27-year-old andrew philip cunanan now the bureau's prime suspect. the question now, what's driving cunanan? ♪ >> gianni discovered south beach by accident. he and antonio, his partner, were on their way to cuba. the flight was delayed. >> he had his cab driver take him for a drive around south beach. >> he fell madly in love with the town. it was everything. if pretty and you owned a pair of roller skates or a bicycle, you wer

. >> andrew cunanan makes the top ten fbi list. >> reporter: what led andrew cunanan to gianni versace's door? two decades later people are still trying to connect the dots. >> i have a beautiful house. i have a beautiful life. but that is the media. what i desire is more. >> gianni versace was at the pinnacle of his career in 1997. >> reporter: little did he know that 'killer at the center a nationwide manhunt on the top of the fbi's ten most wanted list was about to cut that career short. >> if you talk about fate, you had a man on the east coast of miami beach who loved america because he thought it was safe. on the west coast you've got a dirt-bag street hustler who's making his way across the country. >> reporter: andrew cunanan grew up in san diego, the youngest of four children. >> he was the chosen one. he was the prince. he had an iq of 147. he was the kid that was going to succeed out of all their children. >> he was my father's pride and joy. he really was. >> he got everything that he needed. my dad gave him a sports car. and actually, he had the master bedroom. >> he went to

and cunanan's motive?nan singled out gianni versace to murder because he was jealous of the lifestyle. i think he said i'm going down sometime so i want to go down in history. >> he wanted to be bundy. he wanted to be dahmer. he wanted the recognition. he felt he deserved it. >> reporter: tonight we'll take you inside the final stages of the manhunt as miami police finally close in on cunanan who had been hiding on a houseboat across from the fontainebleau hotel as he turns the gun on himself. >> john walsh thought he singled out versace but did they have any relationship? >> that's the enduring question and mystery. there are those that say they were close and they had met and he was a houseguest at versace's say the two never met. he never met the man who wound up killing him. >> after 20 years still a mystery. fascinating stuff, full report on "20/20" at 10:00. >>> coming up next in our big board the summer blockbusters that could take home a top oscar. the early buzz coming out of hollywood. that's nex

cunanan later took his own life.f-x channel is currently filming an american crime story show based on the versace murder. (justine) turning to weather now, meteorologist lawrence karnow has our forecast. lawrence karnow: another weekend, another round of hot, triple digit temperatures for part of the bay area. it's been a hot summer so far and today was no exception. highs soared into the 100s in many of the interior valleys. but it was almost 40 degrees cooler at the coast. heat advisories are up once again away from the coast and bay as temperatures will head back into the 90s and low 100s again tomorrow. we're also seeing a few monsoonal clouds sweeping across our skies too. you can see the big ridge of high pressure building into california. the desert air will stick around for another day before the sea breeze strengthens to cool us down. it will be very hot in the central valley. highs in sacramento could hit 106 degrees. air quality is also suffering and becoming stagnant. it will be hot again tomorrow with t

so what drove cunanan to murder and is there a connection between the victims. 20/20 goes inside thed of a serial killer. watch the investigation tonight at 10:00 p.m. right here on 6abc. it's right after what would you do and be sure of course to stick around for "action news" at 11:00. >> ♪ fios is not cable. and we believe everyone deserves faster internet. so with fios gigabit connection, you get amazing download speeds up to 940 megs 20 times faster than most people have. and it's just $79.99 a month online for the first year. switch to fios gigabit connection with tv and phone for $79.99 a month. plus hbo for one year and multi-room dvr service for two years. all with a 2-year agreement. and switching has never been easier. get out of your contract with up to a $500 credit to help cover your early termination fee. go to fiosgigabit.com. ostriches don't really stick their heads in the sand. a peanut is not a nut. and a real john deere is actually real affordable. you learn something new every day. the surprisingly affordable john deere e series tractors. now you can own america'