SpongeBob SquarePants: The Broadway Musical scrambled aboard a lifeboat Tuesday and it looks as if it could float at least until the Tony Awards in June.

The $20 million musical about colorful creatures under the sea was, many on Broadway thought, headed for that iceberg dead ahead. Advance ticket sales were anemic, and many Broadway insiders were dismissive of a kiddie cartoon turned into a musical.

And yet Mondays opening-night crowd of skeptics were charmed by the sets, Tina Landaus direction and a kid youve never heard of whos destined to be a star: Ethan Slater, the 20-something playing SpongeBob.

Some tough critics were charmed, too, giving the show surprisingly good reviews. As one production staffer said, We were prepared for the worst, but when the reviews came out we were, frankly, stunned.

Viacom, which owns the SpongeBob franchise, is about to throw some big marketing money at the show. Sources say Viacom was holding back out of concern that SpongeBob wasnt selling; although the long-running TV show has made billions around the world, it opened with just $3.5 million in the bank. Rumors were swirling that Viacom was going to pull the plug by the end of the year.

But at a production meeting Tuesday, Viacom executives arrived smiling. They dodged a bullet, and while I cant say they have another Lion King on their hands, they have a show worth fighting for.

The plan is to exploit an untapped market: families who want to go to the theater, but whove been scared away by skyrocketing ticket prices and the sense that Broadway is only for the 1 percent.

SpongeBob has lots of tickets to sell at a reasonable price. Before the show opened Monday, it was averaging $78 a ticket. Thats clicked up to about $98, which is still a steal compared to what people are paying to see Bette Midler in Hello, Dolly! and Bruce Springsteen in that little show of his.

Theres a market theyre going for, and they should, says a top theater executive. Will they make back $20 million on Broadway? No. But the show is good; there will be a tour, and it can be done all over the world.

Bikini Bottom is open for business. Youre not going to sail first class on the Cunard Line thats for people who can afford Hamilton but theres much fun to be had with SpongeBob, the Carnival Cruise ship of Broadway.

Inside Broadway baseball here, but lets go for it: Producers are suing casting directors who are trying to form a union. The producers are carrying a big stick and making loud noises through their trade organization, the Broadway League.

But the actors arent happy. Many owe their careers to casting directors such as Bernie Telsey, Geoffrey Johnson, Jay Binder and Wendy Ettinger. Theyre going to support the people who discovered them, and while their union, Actors Equity, isnt saying much now, a debate is raging. Things could get ugly. Casting directors might not show up for work, and the actors and their union may well support them.