Horrible Histories presents a collection of some of history's finest songs, as Rattus attempts to put together his own festival (the delightfully named Glastonsmelly). From singing poos to tuneful Warlords, there's something for all musical tastes and Rattus has somehow also roped Brad from The Vamps in to help him out, although rather than playing live on the main stage, Brad's role seems to be more about unblocking the toilets just behind it.