Billionaires George Soros and Michael Dell have been dragged into a nasty lawsuit against former NBA great Magic Johnson over his prepaid credit card, the Magic Card.

The moguls are principals of OneWest Bank, which entrepreneur Reed Wallace is accusing, along with the former NBA great Johnson, of stealing his concept for a Magic-backed credit card.

Wallace has claimed in court papers that he had a deal in place with Johnson through his Celebrity Cards International business to market a similarly named Magic Cash Card.

But, Wallace says, Johnson stabbed him in the back by making another deal with the Southern California-based OneWest to launch its own Magic Card venture.

Wallace’s lawyer, Robert J. Hantman, wrote in documents filed in Miami District Court that Wallace believes “George Soros and Michael Dell . . . have relevant and material information” in the case.

“We want to know what [Soros and Dell] know and when they knew it,” Wallace told Page Six. “Did Magic inform them or not [that he had a deal with Celebrity Cards International]? I’m a little guy. I’ve poured everything I had into this [venture]. How can I have enough money to fight these billionaires?”

Wallace is claiming trademark infringement, unfair competition and other charges. He claims that in 2004 he’d sold 2,000 of his Magic Cash Cards before the partnership fell apart.

Wallace added that, two years ago, OneWest had 30,000 on the market, which he estimates would bring in $3.6 million per year in profit.

Johnson has denied Wallace’s claims in court and filed a counterclaim, alleging that Wallace abandoned the Magic Card trademark, which left him free to make his own OneWest deal. Johnson’s lawyers also allege Wallace made “false and misleading” statements to Johnson about their deal.

Hantman, as well as reps for Johnson, Soros, Dell and OneWest didn’t return requests for comment.