The 31-year-old 'Downton Abbey' actress, who plays Lady Mary in the drama, says she can't stop herself from grabbing the microphone and having a sing-a-long when she's had a drink of alcohol, reported Contactmusic.
"It's starts with something like 'Back To Black' ... Then I will have a drink - because everyone has a drink when they are doing karaoke.
"Then it'll be 'Total Eclipse Of The Heart', and by the end of the night I'll be desperately trying to do Whitney Houston, which never goes down very well for anyone," Dockery said.