Jimmy Savile thought he was "untouchable" and would regularly walk in on vulnerable Broadmoor patients while they were in the bath, it has been claimed.
The former star had "total" access to the high-security hospital in Berkshire - where he would walk in on females as they bathed, a former patient from the 1970s said.
His former personal assistant Janet Cope also claimed that Savile had free rein of Broadmoor, where she accused him of working to gain access to high-profile criminals.
She told ITV's Exposure: "Jimmy was untouchable.
"(He) was very proud of the fact that he spoke to all these very high-profile poorly criminals.
Ms Cope said that although she had never seen him abuse anyone, he was a controlling person.
She added: "I knew how he operated so I was very wary of him and I felt there was an undercurrent, there was a bad side, which not many people saw."
At Stoke Mandeville Hospital, Ms Cope said Savile held a position of real authority, adding: "He controlled everything. He controlled me. Everybody was - I'm going to use the word frightened - of him."
Savile, a former BBC TV presenter who died last year, has been accused of hundreds of allegations of child sex abuse and rape.
A former female patient told the programme Savile would walk in while female patients were having baths.
She said: "He would come in when you'd be having a bath...he would just walk in."
Speaking anonymously, she added the star once tried to touch her breast - and when she reported him she spent months in solitary confinement.
Former Conservative MP Edwina Currie told the programme she was "fairly sure" that Savile suggested himself for the role at Broadmoor in the 1980s.
She said: "He would have been seen as an extremely useful person and to have a high profile doing this would have been so much the better.
Ms Currie said that Savile unearthed a series of problems at Broadmoor and believes he planned to use information to blackmail staff there.
"We gave him every instrument that he needed in Broadmoor to prey on some extremely damaged individuals," she added.
"If Savile was alive now I would want to see him locked away for the rest of his life."
Lawyer Liz Duck told the programme she was representing nine women who claimed they were abused by Savile at Stoke Mandeville Hospital.
"Some of them have had their lives destroyed (by Savile)," Ms Duck said.
"Several of the victims did report matters to members...no action was taken."
Savile's estate has been frozen in the wake of mounting sexual abuse claims.
Jimmy Savile in 1961 around the time he was working for Radio Luxembourg. He is at London Airport with Pan American stewardess Birgit Johansson with two gold discs; one is for American singer Elvis Presley for having sold one million copies of "It's Now or Never" in the UK, and the other is for Presley's manager, Colonel Tom Parker
Cilla Black and Jimmy Savile before a Variety Club Luncheon at the Savoy Hotel. Taken in 1964, the year Savile became the first presenter of Top of the Pops
Two women have come forward with allegations from the 1960s, one who was 14 and another who was a teenager when she claims Savile sexually abused her in Scarborough
Savile in 1969 with Physically Handicapped and Able-Bodied (PHAB) member Erika Mentz from Germany and other PHAB members at a dance at Devonshire House
1969 also saw Savile begin volunteering at the Stoke Mandeville Hospital for specialist spinal injuries. He would later be given a room there
Jimmy Savile presenting a cheque to children on behalf of the NSPCC in 1969
The 1970s saw Savile start volunteering at Leeds General Infirmary and...
... Broadmoor secure high-security psychiatric hospital. Allegations by former patients have been made against Savile although ex-workers have disputed the idea that he could have been left alone with anyone whilst working there
The 70s also saw the start of Jim'll Fix It. Allegations from this period include Caroline Moore, a 13-year-old patient at Stoke Mandeville hospital in 1971, who says Savile "rammed his tongue" down her throat and another allegation accuses Savile of molesting a brain-damaged teenage patient at Leeds General Infirmary in 1972
The 1980s saw the continuation of Top of the Pops and Jim'll Fix It as Savile became a much loved household name. Two allegations relating to this time include one from a then-15-year-old girl (not pictured) who made a complaint of abuse by Savile in Lancashire. Pictured is 12-year-old Rebecca Heap
Savile at the Stoke Mandeville hospital with injured children from Beirut in 1987
Savile was knighted in 1990 and continued his charity work throughout the decade
Savile was questioned in 2007 by police about allegations of sexual abuse but the Crown Prosecution service says there is not enough evidence to warrant a prosecution
A 2008 police report into abuse at the Haut de Garenne children's home in Jersey names Savile, although this is never made public
Savile re-united with his Jim'll Fix It chair in 2009. The previous year Sussex police received a complaint of sexual assault but went on to say the victim was "unwilling to co-operate in any investigation"
Jimmy Savile is found dead at the age of 84 in October 2011. He is buried in Scarborough
In December 2011 the BBC drop an investigation by Newsnight into the allegations of sexual abuse by Jimmy Savile. Three tribute programmes are aired instead
ITV airs a documentary, 'Exposure, the Other Side of Jimmy Savile', in which a number of women claim they were abused by Savile as youngsters, including Karin Ward (pictured)
Within days of the documentary, many more allegations surface. By the 9 October Peter Spindler of the Metropolitan Police tells the BBC: "It is quite clear from what women are telling us that Savile was a predatory sex offender"
11 October 2012 and George Entwistle, Director General of the BBC, asks journalists why the Newsnight programme was dropped as police from Tayside, Greater Manchester, Lancashire and North Yorkshire police say they are investigating allegations going back to 1959
12 October and police reveal they have 340 potential lines of inquiry
15 October sees a man come forward alleging that Savile abused him when he was a nine-year-old boyscout
Savile's family removed his headstone from his grave and broke it up in the wake of the furore
Jimmy Savile sexually abuses transgender man
A transgender man comes forward alleging that Jimmy Savile 'stuck his hand up his nightdress' while he was a 17-year-old teenage girl at Broadmoor in the 1970's. More here http://www.huffingtonpost.co.uk/2012/10/15/jimmy-savile-timeline-abuse-allegations_n_1966426.html?1350304573#slide=1641388