Originally Posted by Unregistered

Haha. Any proper employment contract worth its salt has a mechanism built in to allow the firm to do something like that, especially if you haven't passed a probationary period or started work.

Even if they indeed breached a term of the contract, exactly what action do you want to take?

You want to be the known as the guy who sued a big 4 firm for rescinding? I'm sure that will do wonders for your job search