Desc: Shark Below Zero: Directed by Mark Woodward. With Heather Bowlby, Sean Boyce Johnson, Warren Joyce, Greg Skomal. Experts Greg Skomal, Heather Bowlby, Megan Winton, and Warren Joyce look into what motivates white sharks to travel to the northernmost edge of their range following the first probable white shark attack in Canada in more than 150 years.