Here is The Guardian's podcast on the 1986 assassination of Swedish PM Olof Palme, a still open investigation which intrigues and rankles Swedes perhaps more than the JFKA troubles the US.
Of interest is the description of the role and character of the private researchers. Transcript included.
https://www.theguardian.com/news/audio/2019/may/27/who-killed-the-prime-minister-the-unsolved-that-still-haunts-sweden-podcast
An MSM headline you'll never see in America: New Evidence:
https://www.theguardian.com/news/2019/may/16/olof-palme-sweden-prime-minister-unsolved-murder-new-evidence