It's the $65 million crime thriller that claims to tell the true story of the most infamous and violent criminal in the history of South Boston, James 'Whitey' Bulger. But 'Black Mass', the upcoming film starring Johnny Depp and Dakota Johnson, has already upset the families of some of Bulger's many victims ahead of its release in September. Steven Davis, 57, of Milton, and his relatives are sure Bulger killed his sister, Debra Davis, in 1981, despite the jury returning a 'no finding' verdict. Following the release of the first Black Mass trailer this week, Mr Davis told The Boston Globe he and his family are upset and offended that people will be profiting from their tragedy. Scroll down for video . Hurt: Steven Davis holds up a photo of his dead sister, Debra Davis, who he believes was murdered by Whitey Bulger in 1981. His family are upset that Bulger's exploits have been made into a move, Black Mass . First look: Davis spoke out following the release this week of the first trailer for Black Mass, which showed Johnny Depp for the first time as Whitey Bulger . Unrecognizable: In the trailer, Depp is completely transformed for the role.  He looks several years older, with grey slicked back hair and his brown eyes changes to a grey-blue. Bulger pictured in a 1973 mugshot, right . Murdered: Debra Davis was the girlfriend of Bulger's second-in-command, and Bulger allegedly killed her because he believed she knew too much about their crime ring, which involved corrupt cops . 'A lot of the families are very, very upset about this,' Davis told The Globe. 'I don't like it one bit. . . . Everybody seems to be profiting off it. 'It's sad for the movie industry, it's sad for the actors.' With Bulger's reign of terror throughout the city from the 1970's, Davis said it was too early to relive such atrocities. 'It's too much hurt still going on,' he told the newspaper. 'It's still too new to the heart for people.' Another major point Davis makes is that the film glamorizes Bulger, who was an FBI informant from 1975 to 1990. 'He was a piece of (expletive) anyway,' Davis said. 'The only reason he had the power to do what he did was because the FBI was protecting him. 'The movie industry and the actors, they're the ones making the money. 'It's another (expletive) slap in the face, that's what we're getting paid. Another slap in the face.' Dead: Debra Davis was 26-years-old when she was killed in South Boston in 1981 . Hollywood portrayal: Black Mass, starring Johnny Depp, is based on the 2001 book, Black Mass: The True Story Of An Unholy Alliance Between The FBI And The Irish Mob, written by Dick Lehr and Gerard O'Neill . Debra Davis was 26-years-old when she died. She was the girlfriend of Stephen 'The Rifleman' Flemmi, Bulger's second lieutenant. Flemmi testified at Bulger's murder trial in 2013 that he delivered Davis to Bulger to be killed. Flemmi had 'blurted out' to his girlfriend about the arrangement he and Bulger had with John Connolly, the corrupt ex-FBI agent who enabled the Winter Hill Gang's criminal activities for years. When news of this got back to Bulger, he decided she had to die, Flemmi testified. Flemmi said he was meant to kill Davis himself, but after luring her to a house in South Boston, he realized he couldn't do it. That's when, he claims, Bulger strangled her to death. After the killing, Flemmi testified, Bulger 'went upstairs and laid down' while he cleaned up the crime scene, WGBH News reported. At his home outside Boston, Steven Davis holds a Magnum 357 bullet he says was given to him by Boston area gangster James ' Whitey' Bulger in 1982--a gesture Davis perceived as a veiled threat from Bulger . They removed her clothes, wrapped her in a tarp and buried her in a makeshift grave. Flemmi said Bulger stood by and watched as he and some other associated dug the grave. However Bulger strongly denied killing Davis and was not found guilty. Black Mass is based on the 2001 book, Black Mass: The True Story Of An Unholy Alliance Between The FBI And The Irish Mob, written by Dick Lehr and Gerard O'Neill. The film also stars Joel Edgerton, Benedict Cumberbatch, Kevin Bacon, Peter Sarsgaard and Dakota Johnson. Bulger topped the FBI's most wanted list for 16 years before he was finally arrested in 2011. He had a long career of run-ins with the law, dating all the way back to when he was just 14 years old. In the early 70s, after spending nine years in prison for armed robbery and truck hijacking, Bulger returned to Boston and joined a prominent Irish mob in South Boston. Captured: Bulger pictured on the left in 2011, after he was finally arrested after 16 years on the run. He is currently imprisoned in a maximum security prison in Florida. Depp on the right . As he became climbed up the rankings of the mob, Bulger was recruited in the mid 1970s to become an informant for the FBI, supplying the bureau with information on a rival crime family. Then in 1997, Bulger was outed as an informant in newspaper reports and he went on the run when his own handler said he was about to be hit with an indictment. For the next 16 years, Bulger evaded law enforcement until he was finally caught on June 22, 2011 at a Santa Monica, California apartment he shared with his longtime girlfriend. He went on trial two years later on 32 counts of racketeering, money laundering, extortion, weapons charges, and ties to 19 murders. He was found guilty on 31 of those charges in August and sentenced to two consecutive life in prison sentences in November 2013. The 84-year-old is currently incarcerated at an all-male federal high-security prison in Sumterville, Florida. Jack Nicholson's character in the Oscar-winning film The Departed is thought to be loosely based on Bulger.
'Black Mass' is a $65 million crime thriller set to be released in September .
Steven Davis says it glamorizes Bulger's crimes and profits from the tragedy of his victims .
His sister, Debra Davis, was allegedly killed by Bulger in 1981 .
However the jury returned a 'no finding' verdict at Bulger's murder trial .