reality visitors to exhibits promising up-close animal encounters -- >> oh, my gosh. >> reporter: -- have seen time and time again. this lion at the mgm grand las vegas lashed out at trainers in front of stunned guests in 2010. and roadside animal attractions across america have seen numerous attacks like this oklahoma boy being pounced on by a tiger cub. all captured by undercover humane society cameras. >> good girl. >> reporter: but for jeff harwell, braving animals others see as dangerous is worth it. >> sometimes we just get caught up in playing. we're not performing anymore. people aren't even there. it's just my tiger and me. >> reporter: john muller, abc news, new york. >> wow. luckily, thankfully no incidents, injuries have been reported, nothing since 1991. >> wow. speaking of things you will never, ever see in life. that's one of them. people thought siegfried and roy