WATCH: Heavy Metal 'Granny' Joins Five Finger Death Punch

Members of Five Finger Death Punch were joined on stage last week by an unlikely fan.

While performing “Jeckyll and Hyde” during a concert in Oslo, Norway, the band got some help from an elderly woman who rocked out – adding backing vocals and playing air guitar.

At the end, frontman Ivan Moody held up the unidentified granny's hand and gave her a hug as the crowd cheered.

Watch it all go down below: