A Very Grammy Christmas 2014

Ariana Grande and Big Sean perform during"A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Ariana Grande

Ariana Grande rehearses for "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Mary J. Blige rehearses for "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Pharrell Williams performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Ariana Grande performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Sam Smith performs during "A Very Grammy Christmas."

Maroon 5 performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

LL Cool J hosts "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Tim McGraw performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Mary J. Blige performs during"A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Maroon 5 performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Pharrell Williams performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Ariana Grande rehearses for "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Tim McGraw performs during "A Very Grammy Christmas," airing Dec. 5, 2014 on CBS.

Sam Smith performs during "A Very Grammy Christmas."