[ dogs barking ] >> so, in 2011, sam contacts tyson kilmer, who has a reputation for working with dangerous breeds. his hollywood clientele includes rob lowe and mike tyson, but none impresses him like sam simon. >> the first meeting he had with sam, tyson came back and went, "i met my hero. i met a guy that's doing way more than i am with animals." it was a bromance. >> alison kilmer is tyson's wife. >> was it more than just about the dog? >> oh, yeah. tyson knew right away that sam was someone that was gonna mentor him. >> still, tyson hesitates taking the columbo case. >> i had stopped working with that breed a few years prior, just because of the volatility and the liability issues around them. >> i'm sure that training aggressive dogs is dangerous. where is columbo on the scale? >> if it's a scale from 1 to 10, columbo's a 12. >> tyson says he makes an exception for columbo, when simon convinces him that health issues, like painful hip dysplasia, explain why he's such a bad dog. so, it's not just behavioral. it's also medicine? >> that's correct. >> simon's already paying for the best