Robert Plant & Alison Krauss perform 'Can't Let Go' #Video

{no longer available}: null/3x8P74b
Robert Plant & Alison Krauss join this week’s Saturday Sessions. The two first sang together at a 2004 tribute and decided to try recording together. The result, "Raising Sand," was an award-winning blockbuster. Now they're out with a new album "Raise the Roof.” From Nashville, Robert Plant and Alison Krauss perform "Can't Let Go."