Jack O'Connell in '71.

Jack O’Connell delivers a harrowing performance in ’71, an unrelenting thriller that has been flying mysteriously under the radar.

Yann Demange’s directorial debut is a tense experience from beginning to end, using early ’70s strife in Ireland as its backdrop. New soldier Gary Hook (O’Connell) is on his first mission in Belfast when he gets separated from his group and winds up witnessing horrific violence. The film becomes a chase movie as Hook tries to make it back to his barracks.

O’Connell, who had a breakthrough year in 2014 thanks to Unbroken, commands the movie in the central role. Demange shows an aptitude for extreme tension and heart-wrenching violence. This will surely stand as one of the year’s better directing debuts.

The supporting cast is strong, including Sean Harris as an undercover agent with murky political leanings.

Special Features: While the film is not yet available on DVD and Blu-ray in the United States, you do get some features if you choose to purchase the film on iTunes, including a director’s commentary and a photo gallery.

The film is available on demand and via online sources including iTunes and Amazon.com.