Criminologist Mark Williams-Thomas has told Daybreak that Jimmy Savile got involved in every single element of society.
He said: "He organised it in such a way that it always gave him access to children or the opportunity to offend."
Williams-Thomas however admitted that some of the charity work Savile did was geniune.
He said: "The problem was that you don't know where you draw that line in respect whether is was genuine or whether it was for an alternative motive."
A former female patient at Stoke Mandeville Hospital told ITV's Exposure that Jimmy Savile would walk in while female patients were having a bath.
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.
Jimmy Savile's former personal assistant, Janet Cope, told ITV's Exposure 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."
Anyone affected by the issues raised in ITV1 Exposure Update: The Savile Files can contact the NSPCC Helpline on 0808 800 5000 or their local police force.
You can also contact the National Association for People Abused in Childhood by calling 0800 085 3330.
The Helpline is open 10.00am-9.00pm Monday to Thursday and 10.00am-6.00pm on Fridays
Sir Jimmy Savile's former PA, Janet Cope, told ITV1 Exposure, "Jimmy was untouchable".
Ms Cope claims Savile had "total" access at the high-security hospital and "was very proud of the fact that he spoke to all these very high-profile poorly criminals".
ITV1 Exposure Update: The Jimmy Savile Investigation will be broadcast at 10.35pm tonight.
Former Conservative MP Edwina Currie told ITV1 Exposure she was "fairly sure" that Sir Jimmy Savile suggested himself for the role at the high-security Broadmoor Hospital in the 1980s.
"He would have been seen as an extremely useful person and to have a high profile doing this is would have been so much the better", she said.
Ms Currie alleges that Savile claimed he had unearthed a series of problems at Broadmoor, and she 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.
ITV1 Exposure Update: The Jimmy Savile Investigation will air tonight at 10.35pm.
Sir Jimmy Savile's PA for 28 years has spoken to ITV1 Exposure about his rise to fame, and his ability to associate himself with the great and the good.
Going through old pictures and files with investigator Mark Williams-Thomas, Janet Cope explains what Savile was like when he was with them.
ITV1 Exposure Update: The Jimmy Savile Investigation will be broadcast tonight at 10.35pm.
Mark Williams-Thomas, the criminologist who led the initial ITV Exposure documentary that revealed the Jimmy Savile abuse claims, has tweeted that a follow-up programme will be broadcast in just under two weeks' time.
ITV's Exposure reveals footage of honour killing victim Banaz Mahmod telling police she fears for her own safety months before her murder.Read the full story ›
Mark Williams-Thomas, a former police detective and presenter of the Exposure documentary that made public the Jimmy Savile abuse claims, told Daybreak that the investigation into Savile is "a watershed moment in child protection."
"I hope the legacy of my film is one that allows people to have the confidence to come forward," he said.