Critical mass - Steve Martini

Joss Cole, a burned out public defender from LA, has opted for a quieter life in Washington State. Then into her office walks Dean Belden in search of a lawyer to help him set up a business. Within days Belden appears before a federal grand jury and, just minutes before testifying, he is killed.

Meanwhile, Gideon van Ry, a nuclear fission expert in California, is troubled by the failure to account for two nuclear devices missing from the former Soviet Union. Under a false bill of lading, they were shipped to a company called Belden Electronics, and Gideon's only lead is the lawyer who incorporated Belden Electronics - Joss Cole...