A panic-stricken young woman tries to convince Kirkendall and Russell that her twin sister has become the victim of foul play; and Sipowicz and Sorenson investigate an immigrant's possible involvement in the murder of his wealthy but unpopular wife.

Once again, Diane Russell reluctantly finds herself in a dangerous standoff with undercover narcotics agent Harry Denby, who may know the truth about Kirkendall's ex-husband. Meanwhile, Sipowicz and Sorenson investigate a husband's claims about his wife and the ex-con they're housing, and Greg and Jones uncover a home-repair scam.