Interestingly enough, both films were written by their directors. As for eXistenZ, according to Wikipedia:
The film's plot came about after Cronenberg conducted an interview with Salman Rushdie for Shift magazine in 1995. At the time, Rushdie was in hiding due to a Fatwah being put on his life by Muslim extremists due to his controversial book The Satanic ...
From the Wikipedia page for The Tunnel:
The Tunnel (French: Tunnel) is a British-French crime drama television series adapted from the 2011 Danish-Swedish crime series The Bridge (Broen, Bron).
From the German Wikipedia page for The Pass:
Inspiriert wurden die Drehbuchautoren von der dänisch-schwedischen Serie Die Brücke – Transit in den Tod