Mr. Lemon agreed in January to take his new show to X, which Mr. Musk owns, as part of the platform's effort to create premium content to attract advertisers. Mr. Musk agreed to pay Mr. Lemon $1.5 million annually to produce videos exclusively on X, to give him a share of the advertising revenue from his videos and to award Mr. Lemon additional cash incentives as his account gained followers, according to the lawsuit, which was filed in California Superior Court in San Francisco.

Mr. Musk also agreed to be Mr. Lemon's first guest on the show. But the March interview quickly devolved as Mr. Lemon asked the billionaire about his drug use and politics. Shortly after, Mr. Musk canceled the deal.

Mr. Lemon did not sign a contract cementing the agreement, which he believed would be a launchpad for his new show after CNN fired him last year, the lawsuit said. Mr. Musk told him during a phone call that there was no need to "fill out paperwork" and reassured Mr. Lemon that X would financially support the show even if he did not like the views Mr. Lemon espoused, according to the court filing.

"X executives used Don to prop up their advertising sales pitch, then canceled their partnership and dragged Don's name through the mud," Carney Shegerian, a lawyer for Mr. Lemon, said in a statement.

X and Mr. Musk did not immediately respond to requests for comment.

After Mr. Musk bought X in 2022, advertisers fled in droves as he posted erratic messages to the site and researchers reported a surge of misinformation and hate speech on it.

Linda Yaccarino, X's chief executive, came up with the idea to create shows for the site, teaming up with Mr. Lemon and other household names to offer premium content that advertisers would feel comfortable appearing alongside. In January, she announced deals with Mr. Lemon, former Representative Tulsi Gabbard and the sportscaster Jim Rome. (Mr. Rome's show has since debuted on X. Ms. Gabbard's has not.)