Deborah Graham, the protagonist of Anthony Hyde’s new, fast-paced yarn, is a Toronto stockbroker. As smart as she is beautiful, she is a sweet, old-fashioned girl who kisses a handsome stranger while holidaying in Venice: “[H]er knees went all weak, and only his hand, slipping down to the small of her back, held her up.” (It takes an act of will to get past this bit of purple prose, but things do improve.)

The ensuing love affair is torrid, but long distance through most of the book. When a client of Graham’s is shot just minutes after ordering a stock from her over the phone, Graham lands neatly, if not too credibly, in the middle of a murder case.

It’s no ordinary murder, however. Sinister subplots multiply when Graham discovers links between her doctor/researcher boyfriend (formerly the handsome stranger in Venice) and the stock the victim wanted to buy. The ante goes up with the arrival of powerful interests from the scientific community that are trying to get rich peddling a new birth-control drug to the Third World, a concoction that allows women to conceive only male children.

Graham joins forces with Charlaine Daniels, a doctor in a Baltimore ghetto who unknowingly tested the drug on her patients, believing it to be a vaccine against measles, mumps, and rubella. When the police drop the murder investigation, the two women take matters into their own hands.

Things get more complicated after that. There is a brutal rape scene, and the threat of a population explosion greater than ever before predicted. There is a subtle undertone of anti-feminism, and a not-so-subtle metaphor for an uprising of the Third World poor. Overtones of covert dabbling by a U.S. government agency add to the menacing air.

Although it is still somewhat rare for a male writer to create a female protagonist, and rarer still that he is successful, Hyde beats the odds with his credible portrayal of Graham and Daniels. The plot sails along, but Hyde’s rendering of a gender-selective birth-control drug isn’t really believable, and neither is his portrayal of an unscrupulous drug company’s attempts to manipulate populations on a global scale. A well-written novel that wanders into the SF realm can test the limits of credibility without appearing to; Hyde’s Double Helix, however, shows clear signs of strain.