(CNN) Twenty men have filed suit against the Madison Square Boys & Girls Club, alleging the organization was negligent in allowing alleged sexual abuse by two staff members, one of whom was depicted in the 1978 memoir "The Basketball Diaries."

The complaint alleges gym director Nicholas "Lefty" Antonucci and "pool doctor" Dr. Reginald Archibald routinely and systematically abused boys at the club, and that the club "failed to address sexual abuse which was occurring in plain sight."

Antonucci was featured as Lefty in "The Basketball Diaries," a memoir by Jim Carroll, the lawsuit states. The book was adapted into a movie starring Leonardo DiCaprio.

Quoting from Chapter 1, the suit relates Carroll's assessment of Antonucci:

"Although he is a great ball player and a strong guy, he likes to do funny things to you like put his hand between your legs. When he did this I got keenly suspicious. I guess I better not tell my mother about it."

The men who filed suit, who were between 6 and 18 at the time of their alleged abuse, were members of the organization -- then known as the Madison Square Boys Club -- between 1950 and 1980.

The suit has been filed under New York's Child Victims Act, which has opened a one-year window to file suit over childhood abuse allegations that would otherwise be blocked by the relevant statute of limitations.

An attorney who represents the alleged victims says they didn't report the abuse at the time because of their age, family circumstances and the cultural ignorance of child sex abuse at the time.

"It was a vastly different time," attorney James Marsh told CNN.

According to the suit, Antonucci regularly fondled young boys at the MSBC clubhouse, often in sight of other boys.

The suit also alleges he would invite some boys to sleepovers on the clubhouse roof, at which he was the only adult present. He would require the boys to play games, the suit alleges, that involved "tying the boys' penises together and throwing cold water on them." If the boys lost a game, the suit alleges Antonucci would punish them, in one case by using "ketchup and mustard to masturbate the loser," again with others watching.

The suit accuses Archibald, who at one point sat on the club's board, of masturbating and otherwise abusing boys during a required annual physical. He also allegedly photographed the boys naked, occasionally displaying the photos in his office, among other allegations.

CNN has reached out to the Madison Square Boys & Girls Club for comment.

Archibald died in 2007.

It is unclear whether Antonucci is still alive.

In a January statement on the club's website responding specifically to allegations against Archibald, the club says it is conducting an investigation.

"We are deeply disturbed by these allegations and are taking this matter very seriously. The Board of Trustees has retained Nancy Kestenbaum of Covington & Burling LLP to conduct an independent investigation into Dr. Archibald's conduct at, and past association with, Madison," the statement reads in part. "Nothing is more important to Madison than the safety and well-being of the children we serve. We have strict policies and procedures in place to make sure our club members are safe at all times and that our staff is trained to identify and report any signs of abuse."

The statement asks any former members with information to share to contact Kestenbaum.

When asked about Antonucci, the club provided the following statement to CNN.

"Although we cannot comment on the specific claims filed, we recognize that as an organization -- and a society -- we have a responsibility to make sure victims of abuse are heard, acknowledged and empowered to heal. The Madison Square Boys and Girls Club applauds the courage of all those who have come forward to describe their painful experiences, which strike at the very core of our organization's values."

Jennifer Freeman, an attorney for the 20 men suing the club, spoke to CNN on Wednesday.

"This was in plain sight," she said. "They were abusing kids in plain sight."

The suit notes the New York County District Attorney's office investigated Archibald "in or about 1960" for abuse allegations surrounding his work as a physician at Rockefeller University Hospital. "As far as I know there was a grand jury subpoena issued," Freeman said, however, "he was not charged."

Freeman also provided a 2019 report from an independent investigator documenting allegations against Archibald during his time at Rockefeller University.