By Ryan Faughnder, Los Angeles Times

LOS ANGELES — An average of 3.5 million viewers tuned in for Sunday’s season finale of “True Detective,” the HBO crime anthology starring Matthew McConaughey and Woody Harrelson, according to Nielsen.

That’s the biggest audience ever for the 9 p.m. ET cable drama and 50 percent higher than the 2.3 million who watched the show’s premiere.

The show’s big closer faced heavy competition on cable and broadcast networks, including the premieres of ABC’s “Resurrection” and Fox’s “Cosmos,” along with an episode of the AMC hit “Walking Dead.”

McConaughey and Harrelson played investigators hunting for a Louisiana serial killer.

A total of 11 million people have watched the series to date, which marks the highest gross viewership for a first-season HBO series since “Six Feet Under” hooked 11.4 million in 2001.

Photo: JasonParis via Flickr