It may not have happened at 2:17 a.m., but “Weapons” has reached a major box office milestone.

Director and writer Zach Cregger’s horror hit, about 17 school children from the same class who mysteriously all go missing in the middle of the night, has crossed $100 million at the domestic box office. That’s a great achievement for a low-budget horror movie, which has also been No. 1 at the box office for the past two weeks.

It took two weeks for “Weapons” to reach $100.3 million domestically, a fantastic milestone considering it only cost $38 million to produce. Internationally, the movie has made $72.3 million, putting its worldwide total at $172.6 million.

It’s been a great year for original horror and Warner Bros. specifically. The studio had another R-rated major hit earlier this year with Ryan Coogler’s vampire horror movie “Sinners.” Coogler’s movie stands at $365 million worldwide, including $278 million domestically; it opened to $48 million domestically,…