Nightmare (Korean: 악몽; Hanja: 惡夢; RR: angmong) is the debut single album recorded by South Korean girl group Dreamcatcher.

It is the first release from the group following the rename of the band[1] and addition of new members, Handong[2] and Gahyeon.

[3] The EP was released on January 13, 2017 and debuted at number 20 on the Gaon Album Chart.

In mid-2016, Happy Face Entertainment announced that the group would re-brand as Dreamcatcher with two additional members; Gahyeon and Handong, In the following months, Happy Face Entertainment released an official teaser image and announced that the group will debut in the first half of 2017.

[4] On January 13, 2017, Happy Face Entertainment released Dreamcatcher's first EP "Nightmare", with their title track "Chase Me".