Keegan Allen is an actor, photographer, and author. He played the role of Toby in the hit series "Pretty Little Liars," and is the author of two best-selling books. After bold performances in feature films such as "King Cobra" and "No Escape"—also known internationally as "Follow Me"—he is now starring as Liam Walker in "Walker," the Texas Ranger reboot on the CW. Join Keegan Allen and host Nicholas Ryan Howard in their hike through the snow, deep in Sequoia National Park.