Stephen Sondheim’s dark musical about presidential assassins has become a classic since it was first staged in 1990. That was the same year that Falcon Theatre began producing shows in Greater Cincinnati. In 1998, Falcon’s staging of Assassins put the company on local theatergoers’ radar. You know the names: John Wilkes Booth, Squeaky Fromme, Lee Harvey Oswald and more — all disgruntled, unbalanced people whose twisted path to the American Dream involved shooting a president. In this fascinating show they converge, commiserate and conspire, each with music from his or her moment in American history. It’s a strange tour de force.