It sounds like a scenario straight from central casting. A liberal Hollywood mogul and conservative Texas billionaire are among the exclusive 25-member million-dollar check writing club whose members forked over additional cash for super PACs in September, according to a recent Sunlight Foundation analysis.

Dreamworks CEO Jeffrey Katzenberg and Texas nuclear waste entrepreneur Harold Simmons are also among Sunlight's Stealthy Wealthy, our continuing series that looks at the giving habits of influential political donors. For the month of September, Katzenberg and Simmons were the only Stealthies who showed up as donating to super PACs — but it's always possible for donors who want to go completely under the radar to funnel their contributions to political nonprofits, whose contributors remain unreported. 

Katzenberg last month sent $1 million to Priorities USA Action, the super PAC backing President Barack Obama's reelection bid, and $25,000 to the House Majority PAC, the super PAC working to elect Democrats in the House, bringing his total contributions to Democratic super PACs this election cycle to $3.15 million.

Simmons, the CEO of Contran Corp, bankrolled the conservative super PAC American Crossroads  $2.5 million, while also sending the pro-Romney Super PAC Restore Our Future a half-million-dollar check. That brings his contributions to Republican super PACs in this campaign cycle to an eye-popping $18.2 million.

Like other "Stealthy Wealthy" donors, this political odd couple have something besides deep pockets in common. Like most of the nation's wealthy, they've used campaign contributions as part of their strategy in building their massive business empires.

"Stealthy Wealthy" is the nickname we've developed for these billionaires, whose names you may or may not have heard of, who seek to influence not just elections, but their own personal fortunes, through their exorbitant donations. Sunlight will be watching to see how they extract the returns for their investment.