Alanis Morissette, Ellen DeGeneres Dressed Up Like Taylor Swift

Taylor Swift - H 2015
AP Images

You oughta know that this happened at Monday's concert at L.A.'s Staples Center.

So far, everyone from Kobe Bryant to Julia Roberts has made a cameo appearance on Taylor Swift's 1989 World Tour (including her infamous girl squad — because duh). At her L.A. concert last night, Swift added to her long list of increasingly random-seeming guests (Matt LeBlanc? OK.) by inviting Ellen DeGeneres and Alanis Morissette to join her onstage at the Staples Center.

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Both Morissette (who dueted on "You Oughta Know" with Calvin Harris' main boo thang) and DeGeneres dressed for the occasion — meaning they matched the pop star in similarly skintight outfits.

Morissette introduced a whole new generation to her angsty ballad while clad in leather pants, chunky black boots and a black blazer, standing alongside Swift, who wore a black leather jumpsuit.

But the real showstopper of the evening was DeGeneres, who made her glittering onstage debut in a sequined jumpsuit, which she paired with a fringed, hula-esque tutu skirt. The Ellen host and lifestyle-brand pioneer topped the sparkly look like any fashionista would — with plain white sneakers, of course.

Though it's a tough call, we'd have to say that, in this case, DeGeneres really wore it best.