A approaches a law firm and says that they’ve negotiated a settlement in principle with B, and can the law firm please eyeball the final agreement. The settlement will be about $280k and you can keep $5k for 1 or 2 hours of work. A is to be paid by wire upon receipt of a certified check from B made out to the law firm. The certified check arrives and the law firm deposits it. The scam depends on the hope that the firm will mistakenly think that a certified check is like depositing cash, and will therefore immediately wire the balance to A. However, the certified check is forged.
Note: This scam is going on presently, while this post from the North Carolina Bar Association indicates that it has been around since at least May 2008 (and is of course a variation of the ‘classic’ bank frauds). The post contains practice pointers and red flags.