In September, Bank of America wanted to show that, with its acquisition of Merrill Lynch, it knew what it was getting into. Now Bank of America is wants to show it had no idea what it was getting into.

The about-face naturally puts the spotlight on the investment bankers--Fox-Pitt Kelton and J. Christopher Flowers--who advised BofA Chief Executive Ken Lewis on the deal. And at the center is Christopher Flowers, a former Goldman Sachs & Co. banker and prominent investor in banks and financial-services firms, who reverted to...