Nine Muses have revealed the making of their album jacket for 'Lost'!

SEE ALSO: Nine Muses make return with 'Sleepless Night' MV!

The girls returned with 'Lost' and its title track "Sleepless Night" earlier this week, and fans can now check out the making of Nine Muses' sexy album jacket as well as a bonus clip. The members snack and talk backstage, and as always, look beautiful while doing everything!

Check out the making-of video above!