For his first foray into horror cinema the genre in which he would ensure his legacy norman j warren teamed up with critic turned screenwriter david mcgillivray house of whipcord and hammer veteran michael gough the phantom of the opera for a tale of witchcraft and occultism.candace glendenning tower of evil plays a young woman who witnesses the death of her parents en route to visiting her uncle played by gough and cousin martin potter, goodbye gemini'. '.strtoupper('w')hile recovering from the trauma at his isolated estate, she begins to suspect all is not as it seems and that dark magic may be at work...2k restoration, supervised and approved by director norman j warrenoriginal mono audiotwo presentations of the film the director's cut 89 mins and the export version 90 minsaudio commentary with warren and screenwriter david mcgillivray 2004audio commentary with warren and composer john scott 2019before the blood 2019, 29 mins warren recalls his earliest experiences in the film industryall you need is blood 1976, 13 mins vintage 'making of' documentary, presented in high definition for the first timeall you need is blood outtakes 1976, 33 mins rare and previously unseen footage shot on locationcreating satan 2004, 30 mins archival documentary featuring interviews with warren, mcgillivray, actor martin potter, and othersdevilish music 2004, 13 mins archival interview with john scotttwo deleted scenes with commentary by warrencensoring 'satan's slave' 2019, 16 mins video demonstration of the cuts imposed by the british board of film censors in 1976original 'u' certificate theatrical traileroriginal 'r' rated theatrical trailerimage gallery promotional and publicity materialnew and improved english subtitles for the deaf and hard of hearing