When Swedish prog maestros OPETH decided to mark their 20th anniversary, not even the band envisaged the jaw-dropping spectacle that was their mammoth set at London's prestigious Royal Albert Hall.

Romping their way through a three hour set - including 'Blackwater Park' in its entirety - the resulting DVD is a feast for the eyes and ears, and we've got a taster for you right here in the shape of 'Dirge for November'. Available here as the full album version, recorded at the Royal Albert Hall and weighing in at almost 9 minutes, it's time to stop salivating, fill in your details below and get your hands on the MP3!