When Valerie Palmer, a Pan Atlantic air hostess turns up dead, Annie volunteers for a dangerous undercover mission, posing as the murdered woman to help solve the second in a possible series of brutal homicides. Annie, Sam and Ray, working one of Valerie's flights covertly, uncover an unlikely suspect. Then, an invitation to a lurid swingers' party leads to an evening full of sensational surprises - not just for Annie and Sam, attending undercover as a couple, but Lieutenant Hunt also arrives with a special guest to mix it up. Juicy sexual escapades bring the swingers' party to a fever pitch, but will the murderer be revealed? Finally, Annie confronts Hunt with the courage of her convictions about her future at the 1-2-5.