over doofiness. >> polite will always win over doofy. >> after that stunt, neither of them got it, dummy. >> doofies, not dummies. >>> when you think of tractor-trailers, you don't think of precision. but this can be used as a very precise tool. the stunt she's going to attempt is to walk a slack line between two tractor-trailers. >> but they're going to be moving, tell me that, right? >> they are going to be moving, and they're going to be moving towards a tunnel. if she doesn't finish her walk in time, the line gets cut. >> and she goes where? >> crashing down into the road. >> and why? >> it is a commercial to show off the precision of the new volvo fh tractor-trailer. there's a helicopter out there too. i feel like that would make her blow sgloeover. >> just do it really fast. >> here she goes. the trucks get up to speed. scary. >> that's a terrible start. the first few steps she's not off to a very good start at all but she gets back on her feet. >> she is wearing a harness just in case she falls off, right? >> she has a safety line around her ankles. there's the tunnel and she's pr