Conspiracy theory thrillers are almost a genre unto themselves, and the best ones all share a few things in common. The everyday folk caught up in the web should be somewhat relatable, the details of the cover-up should be shocking but believable, and there should be a surprise or two along the way. Closed Circuit barely gets one of those three elements right, but unfortunately it’s the least thrilling of the bunch. A bomb goes off in downtown London killing 120 people, and the evidence leads back to one surviving suspect. He’s quickly arrested by police and identified in the press, and several months later he’s ready for trial. Martin Rose (Eric Bana) is assigned to defend him in court, while another barrister is set to represent him in a secret court where evidence not for public consumption will be discussed, argued over and kept from Rose and the client. But tragedy leads to a change up and Claudia Simmons-Howe (Rebecca Hall) is brought in to handle business in the covert court. Rose and Simmons-Howe had an affair once, and in addition to having wrecked his marriage it also complicates their current assignment. They lie about it but soon discover that their secret is a small fish compared to the leviathan details of the case.