The Big Bang theory. It relates as much to the economy as cosmology. The difference between the two, though, is when that bang takes place. On Mad Money, it’s the end, not the beginning, that matters – at least in this market.

What are we talking about here? Bear markets, like the one we’ve been in, end with a bang, Cramer said. In 1990, it was the failure of Citigroup . In 1996, the Russian financial system collapsed. Long Term Capital Management was the end of 1998’s troubles. Last week, Bear Stearns went bang.

But the implosion of the fifth-largest investment bank wasn’t the only trouble. Fannie Mae and Freddie Mac were on a disastrous precipice and no matter how much the Federal Reserve cut interest rates, the situation just got worse.

Look at this market now, though: The White House freed up Fannie and Freddie to buy more loans, putting the companies back on their feet. This, and the fact that most bad loans will finish resetting in six months, should put housing back on its feet, too, Cramer said. By this fall, he’s expecting house prices to stop depreciating.

And banks now have some breathing room to put those low interest rates to work. They’ll keep savings-account rates low while charging more for mortgages, pocketing the difference. And with Fannie and Freddie back in the game, why not lend? Banks will hand off those loans and take the risk out of their business.

Bob Steel, former Goldman Sachs salesman now working for the Treasury, brokered the Bear Stearns buyout. “This more than anything else, this bang,” Cramer said, “is what I think ended the bear market.” The deal let Wall Street know there was a safety net in place. The feds had a plan to save the next bank that went under and a chance for those who survived to possibly profit.

Now, with the financials on the rise again, other sectors can follow. Cramer recommended Costco , Deckers and Black and Decker , saying retailers and the items they sell are buys. Tech stocks like EMC and IBM that sell to the financials are good, too. Homegamers looking for a financial, rather than a play on one, should consider JPMorgan Chase and Goldman Sachs. Or go with a growth stock with a good dividend like Procter & Gamble. Stocks like PG are most threatened by inflation, Cramer said, but inflation’s less of a worry when financials rally.

A word of caution, though: The market’s already made a huge move. So buy in small quantities until a pullback gives you the chance to load up.

Jim's charitable trust owns EMC and Goldman Sachs.

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