Invasive redback spiders are highly venomous, threatening both people and New Zealand’s native species. A team of scientists is developing a cunning tool to trap male redbacks, by concocting an irresistible spiderweb perfume. We visit 800 captive redback spiders in the lab, learn about their wild mating habits, and check out the “spider arena” where the redbacks’ signature scent is put to the test.