At the end of Penumbra: Oveture what is the thing that takes you away?

[Oscar House]

Uhh, Philip got infected somewhere between Overture and Black Plague, as the symptoms of infection (déjà vu, aural distortion and what have you) don't start appearing until in Black Plague. I would say the Tuurngait captured you because they want to keep expanding the hive mind. When Philip escapes from his captivity, they turn hostile towards him.