T-ara appeared on Davichi concert as guests, gave surprise performance entertaining audience.

T-ara appeared on Davichi concert 'Adios! 2011', which was held at Olympic Park Hall on Dec. 27. Davichi performed Lee Juk and Yoo Jae Suk's 'Apgujung Badboy' wearing vintage old school blazer.

Davichi then went on with T-ara's 'Roly Poly'. But it seemed to be problems including lights going out, speakers going down. No. It was a surprise performance. Stage light came back on and T-ara showed up.

T-ara performed after Davichi's start. T-ara went on with the new song 'Cry Cry'.

In addition, Huh Gak sang 'Please Don't Forget Me as a guest.

Photo: Core Contents Media