After Nicki Minaj made a very memorable appearance on Ellen in September wearing no bra (and rocking a whole lot of cleavage), the talk show host decided that the racy rapper's look would make for the perfect Halloween costume.

Sporting a long blond wig and a fake chest piece on her Oct. 31 show, Ellen quipped: "This year I decided to go as something really scary — half-naked. Of course, I'm Nicki Minaj."

Not to be outdone, Ellen was joined by Alison Sweeney, who arrived as Christina Aguilera from The Voice -- complete with swivel chair.

Watch the hilarious video below!