Martha rehearse a performance piece when a body is discovered in the artificial snow box.
Castle and Alexis follow the emoji instructions from Robyn's phone which leads them to a meeting of an a capella group at a warehouse.
(Song #1 sung during the riff-off) The a capella group start off the riff-off battle.Â
(Song #2 sung during the riff-off) Castle notices one of the singers is wearing the same bracelet as Robyn wore; Ryan and Esposito burst into the warehouse unaware of the non-dangerous scene .
00:01 Martha rehearses a performance as a body is discovered in the artificial snow box.
00:12 Castle and Alexis follow the emoji instructions on Robyn's phone to the meeting of an a capella group at a warehouse.
00:17 Song #2 in the riff-off; Castle notices one of the singers has the same bracelet as Robyn; Ryan and Esposito burst into the warehouse.
Amazon and the Amazon logo are trademarks of Amazon.com, Inc. or its affiliates.
Song previews provided courtesy of Apple Music and Spotify.