Please help, it's been driving me crazy that I can't remember

[koolarion]

From what I can remember the book starts with a man having a picnic with his fiancee on a hill. Afterward he went to his lab, I think he was a physicist, and accidentally opened a rift/portal to another dimension. Long story short, whatever creeped through started infesting people's minds and bodies to the point that it developed a hive mind. I think the book ended with the scientist setting fire to the lab and dying in the fire.


Sorry for the jumbled description, I have read this book sometime before 1995 and 2001.


Thank you!

 

[lokison]

Hellstrom's Hive by Frank Herbert?

 

[koolarion]

Definitely not "Hellstrom's Hive", no government was involved in the book I read.
From what I can recall at one point the protagonist finds a house infested with a thing... merged mutated people in a jabba the hut kind of form.