After School's Lizzy surprise fans with the news of a upcoming duet with Yoon Gun.

On September 21st, Yoon Gun updated his Instagram,"A short break during the recording~ How is our chemistry? kekeke oh~kya with Lizzy~ #chemistry #recording #YoonGun #Lizzy" and uploaded a long a cute selca which he took together with Lizzy.

Lizzy later uploaded the same photo on her Instagram with caption,"Is my chemistry with Yoon Gun oppa bursting out? #YoonGun #Lizzy #Chemistry Burst Out <3"

The duet will be featured in Yoon Gun's 4th album 'Autumn Play' this October.