Why is Burlingame, Kansas so murdery, by episodes?

Burlingame is in Osage County, about 25 minutes outside Topeka, and the show's hosts introduce it as a town the railroad made. It got going in the 1850s, just after the Kansas-Nebraska Act, lost about half its people to malaria in 1856, and became a town properly when the line from Topeka reached it in 1868. The motto is 'where rail crosses trail'. In 2017 the population was 892. It ranks 162 overall and third in Kansas, a lot of league table for a place with 892 people.

All four murders come from one episode, episode 9, aired in 2017, and one date: 28 November 2009. The story is domestic: a fitness instructor met another instructor in 2006, the marriage went downhill, and in January 2009 divorce papers were filed. Four people died, all of them in Burlingame, at 0 miles from the centre, and no other town within 25 miles was claimed. The Burlingame area is one town and one night.