SERIES PREMIERE: Jimmy Fallon’s “Lip Sync Battle” started on Late Night with Jimmy Fallon, the brainchild of guest John Krasinski, his wife Emily Blunt, and their friend, Office co-creator Stephen Merchant. When Fallon inherited The Tonight Show, he brought the “Lip Sync Battle” concept with him, and it’s been a huge hit on YouTube, as exemplified by this sample, presented last month on TVWW’s Video Worth Watching. And now, those segments have turned into a spinoff show, with Fallon and his co-conspirators all making early appearances as guests, and with Grammys host LL Cool J doing the same here. This time around, there are costumes and backup dancers, but it’s still the same old silliness – which means it might be worth your while to find out if you have Spike, and where it is on your cable or satellite roster. Two episodes are shown tonight back-to-back, and in the first, Fallon himself is a contestant, going head to head with Dwayne Johnson. Both take on anthems from female pop stars: Fallon lip-syncs to Madonna’s “Like a Prayer,” and Johnson, a.k.a. The Rock, to Taylor Swift’s “Shake It Off.”