Batman is in the house to play a game of Beach Ball Ballyhoo with Elmo. In search of the perfect bedtime story, Elmo welcomes acapella group Pentatonix, who performs a mashup of lullabies.

Ricky Gervais sings a decibel shattering lullaby to Elmo during a recent appearance on "Sesame Street." Check out if the sardonic "Office" star's ode to the letter "N" is the perfect cure for the ...