Ain't no party like a Carpool Karaoke party -- especially if the party happens to get crashed by a whole bunch of other guests.
In the clip above, Sam Smith jumps in the passenger seat alongside James Corden before getting a surprise visit from a group he loves above all others: Fifth Harmony.
Watch the video for the glorious singing, then stick around for Sam Smith's gleeful reaction when Corden pulls over and the group appear out of nowhere.
