Mafia attorney Morris Shenker joined in 1975, following one of the most extensive routine investigations ever conducted by the Nevada Gaming Control Board.

Nangaku intended to renovate and expand the Dunes, although his plans were derailed by an unusually lengthy control board investigation, which dissuaded financiers.

The Dunes was initially owned by a group of businessmen that included Robert Rice of Beverly Hills, James A. Sullivan of Rhode Island, Milton Gettinger of New York, and Alfred Gottesman, a wealthy theater operator in Florida.

[17][18][19] Businessman Kirk Kerkorian bought a three-percent interest a couple months after the opening,[20] marking his first Las Vegas investment.

[22][23] The Las Vegas Valley had been overbuilt with hotel rooms during a time of lessened demand,[24][25][26] and the Dunes was also the southernmost resort on the Strip, located a considerable distance from other properties.

[44][48] Seven months later, plans were announced for Sullivan and Gottesman to sell the property to Jacob Gottlieb, owner of a Chicago trucking firm.

[56][57] In 1961, St. Louis businessmen Sid Wyman, Charlie Rich, and George Duckworth invested in the Dunes and became the new operators through a lease agreement.

[78] Later in 1969, the U.S. Securities and Exchange Commission filed suit against Continental Connector, accusing it of making inaccurate financial statements regarding earnings at the Dunes.

[82] Rice, Wyman, Duckworth and three other top resort officials were indicted in 1971 by a federal grand jury, alleging that they filed false corporate income tax returns and that they conspired to skim money from the gaming tables.

[88][89] Sullivan's early ownership in the resort was actually held by Raymond Patriarca, and Gottlieb was affiliated with Jimmy Hoffa, president of the Teamsters Union.

The group included San Diego developer Irvin Kahn and partner Morris Shenker, a St. Louis attorney who was representing Wyman and other resort officials in their case.

[98] In 1974, Shenker owned 37 percent of the Dunes through stock holdings in Continental Connector, and he sought to buy out the remainder,[99] prompting the control board to reopen and expand its investigation into his financial background.

[94] In 1975, Tony "The Ant" Spilotro began spending extensive time in the Dunes casino, where he would take phone calls routed to the poker room.

The gaming control board accused him of treating the Dunes as his personal office, and questioned Shenker and Riddle as to why he was allowed on the premises, given his Black Book status.

Specifically, the union stated that the loan could not be granted because Continental Connector owned a trucking company which employed teamsters who had contributed to the pension fund.

[125] Blumenfeld Properties, a Philadelphia real estate development company, made a $145.5 million offer for the Dunes,[126] but ultimately did not purchase the resort.

[127] Financial firm EF Hutton eventually formed a partnership that was interested in purchasing the Dunes, while a separate group led by Kerkorian was also in discussions.

[135][136] While Nangaku waited to receive a gaming license, he hired Dennis Gomes to operate the Dunes, replacing Cohen as president.

The control board encountered difficulty when looking into Nangaku's business associates because of differences in how Japan handles documents, which are generally kept confidential.

[147] Nangaku eventually received a permanent gaming license in May 1991, at which point he was seeking a partner to help renovate and operate the Dunes.

[141] The Las Vegas Review-Journal had written in 1988 that the Dunes had lost its "mystical luster" over the past 20 years, with its high rollers migrating to "more attractive" resorts.

The tower was imploded with great fanfare in an event emceed by Wynn that incorporated his new resort; on his command, a faux pirate ship at Treasure Island shot its cannon several times, simulating the Dunes' destruction by cannonballs as the implosion began.

The Dunes agreed to close its main showroom and convention center in exchange for a county extension, allowing time to raise $13.5 million needed to bring the facilities up to standard.

[71] The foundation measured 80 feet in width,[71][239] and supported two white-colored columns forming a bulbous onion dome or stylized spade shape at the top.

[171] Architectural historian Alan Hess had advocated for saving the sign, although Mirage Resorts stated that it was in extremely poor condition, with demolition being cheaper than preservation.

[259] Comedian Wally Cox was an early entertainer at the Dunes, opening there in July 1955, although he was fired due to poor audience reception.

[276][277] The Broadway show Guys and Dolls, starring Betty Grable and Dan Dailey, also played at the Dunes for about six months, starting in 1962.

[294] Many major professional boxing events took place at the Dunes from 1975 to 1990;[295] notably the May 20, 1983, undercard that featured Ossie Ocasio retaining his WBA's world Cruiserweight title by fifteen round unanimous decision over Randy Stephens, Greg Page beat Renaldo Snipes by twelve rounds unanimous decision in a WBC's Heavyweight division elimination bout, Michael Dokes retained his WBA world Heavyweight title with a fifteen-round draw (tie) over Mike Weaver in their rematch, and Larry Holmes won over Tim Witherspoon by a twelve-round split decision to retain his WBC world Heavyweight title.

The Dunes made film appearances as well, including the 1971 James Bond movie Diamonds Are Forever, in which it serves as the office of Whyte House casino manager Bert Saxby.

[303] The Dunes sign also makes an appearance in the film,[304] and a deleted scene, available on home media releases, takes place in the Dome of the Sea restaurant.