The X-Files (1993–2002, 2016–2018)

This American science-fiction mystery series created by Chris Carter follows FBI agents Fox Mulder and Dana Scully as they investigate unexplained cases involving paranormal phenomena, government conspiracies and extraterrestrial encounters. Blending episodic “monster-of-the-week” stories with long-running mythology arcs, the series explores themes of belief, skepticism and the pursuit of hidden truths. Mulder’s quest for answers and Scully’s scientific perspective form the core of its character-driven tension.

Från IMDB:
Two F.B.I. Agents, Fox Mulder the believer and Dana Scully the skeptic, investigate the strange and unexplained, while hidden forces work to impede their efforts.