There are mysteries afoot on Sesame Street! Grab your detective hat and join your furry friends to solve these whodunits! When items beginning with the letter "R" start vanishing, Detective Alfie Betts is on the case with a little help from Elmo and Abby! Who could the culprit be? Then Elmo and Telly investigate what's making things disappear by following clues and testing their hypotheses.