It’s the 34th year of the Discovery Channel’s “Shark Week” extravaganza. To celebrate the legendary event, Dwayne “The Rock” Johnson will be the first-ever Master of Ceremonies. Comedian Tracy Morgan is interviewing a diver who lost two limbs. Shark diving expert Jimi Partington stars in “Great White Open Ocean” where he encounters a shark. Also, the guys from “Impractical Jokers” will be starring in their own segment.