The mysterious murder of a US senator bearing the identifying trademark of the legendary Soviet assassin'Cassius', forces retired CIA operative, Paul Shepherson to team with rookie FBI agent, the crime to be solved by Ben Geary. Shepherdson is convinced his nemesis is long deceased, but is pushed to take Tom Highland, by his manager on the case. Geary, who wrote his Master's thesis on Shepherdson's search for this killer that is Soviet, is sure that Cassius has resurfaced.