Another week, another grueling battle in our ongoing March Madness series.

We started off this competition with sixteen of the fiercest, most loyal fanbases in pop — and now, we're down to the final four.

In this round? Why, it's the formidable Army of Britney bitch, up against the almighty force known only as One Direction's Directioners.

In the last round, the Britney Army crushed 2NE1's Blackjacks, taking the win with over 58% of the vote. But will they (oops...) do it again?

Similarly, 1D's Directioners reigned supreme in a staggeringly close competition with Katy Perry's KatyCats, narrowly securing their win at just over 50% of the vote. Will they refuse to let the Army drag them down this time around?

It's time to decide: The battle starts now.

This round will end on Wednesday, March 23 at 11:59 PM ET. Vote below!

One Direction Through the Years:

Britney Kicks Off Piece Of Me Remixed Residency: