Getting Back to Natural Hair Color After Dyeing?

I'm looking for some advice. My hair is currently an unevenly faded purple (Arctic Fox Violet Dream), which I absolutely love and have loved in every stage of its fading. Unfortunately, my sister is getting married in a few weeks and wants me, as her Maid of Honor, to have a more natural hair color. Both of us have naturally medium-dark brown hair, so I think it would make the most sense to go back to that color.

My question is, should I try to lift the purple from my hair before I dye it brown, or will I be able to sufficiently cover it if I use a dark enough dye?

Thanks!