bush on fire, cameras roll from above and below. jay jones is one of the teens filming. >> i was in between the bush and chris on top of the cliff filming. i guess mainly the only thing i was worried about was getting the bush lit on fire. i've seen chris jump over that bush before. >> you can hear jay shouting to make the fire bigger. >> that's not enough. >> first we tried lighter fluid. and it wasn't making a dramatic enough effect on the bush. so then it turned to the gas. >> now you got to light it again. >> we struggle for awhile to get it lit. >> just before chris is about to jump, spectators on a boat offer up another challenge. >> somebody dared me to do it naked. so it just went to another level. >> chris is the kind of guy, i've never seen him back down from a dare. >> it finally gets lit.