The magazine became notorious for publishing graphic images of corpses and using shocking headlines such as "Raptola, violola y matola con una pistola" ("He kidnapped her, raped her, and killed her with a gun").
got an unexpected boost in 1964, when it publicised the case of the González Valenzuela sisters, who forced women into prostitution, killed them, and repeatedly bribed authorities to avoid arrest.
The case and the ensuing court process, covered by journalist Jesús Sánches Hermosillo, became a nationwide media circus.
The magazine was cancelled in 1986 due to a political standoff between Publicaciones Llegó and the Mexican government but returned in 1991 as El nuevo Alarma!.
's final issue was published on February 17, 2014, one month before the death of its editor-in-chief Miguel Ángel Rodríguez Vázquez due to a heart attack.