This movie is based on the novel by well known journalist (in the U.K.) Tom Bradby, who also wrote the screenplay. It's a dark thriller that runs a mere 100 minutes, unusually short for the genre; but it still manages to work, without as much of the character and relationship development I would have enjoyed seeing expanded. Bradby has had all the firsthand experience and knowledge on the subject, covering the Northern Ireland goings-on in the 1990's. He skillfully wrote a screenplay that is apolitical, yet retains convincing elements necessary for the movie to be a genuine thriller. The cast was well chosen and the ensemble delivers the goods without reproach.

The opening of the movie brings important context to what will follow next in the movie. It 1973 Belfast, during 'The Troubles', we see young Collette witness the tragedy of the times when her younger brother is killed, collateral damage, and how she is moved by the event. Maria Laird who plays young Collette is an actress I look forward to seeing again soon. Then we fast forward to 1993 when Collette, played by Andrea Riseborough, is now an IRA member; she is apprehended when she planted a bomb in the London Underground, but the IRA doesn't know that for sure. Enters Mac, MI 5 agent played by Clyve Owen, who turns Collette informant. Unbeknownst to Mac, Collette's MI 5 mission is to protect a mole they have in the IRA; Kate Fletcher, played by Gillian Anderson, is Mac's superior but she does not share the information about the existence of a mole, which is something he has to dig up himself, if he's to ensure the protection of Collette. The drama then unfolds. The thriller has just one real twist, but it is a startling one at the end.

I have to warn audiences about the very poor audio levelling in the movie. You see, there are two very critical and short pieces of dialogue without which it will be virtually impossible to understand the movie's denouement. So if you see the movie on DVD/BlueRay or some other device that has pause and rewind features, you'll be fine; you can play back and jack up the volume for those two moments, and you'll know I'm sure when those are. I never get how sound editors can miss that sort of stuff, that which can kill the viewing enjoyment. I'm very glad I didn't see this movie at the cinema, but on my big screen at home instead.

Given the running time of the movie, I was happy enough with the key actors' interpretations of their role, but can't help but think how much better I would have like it if some twenty more minutes could have been added. I hope those weren't just cut out for reasons I don't want to speculate about. Of course, you get that I recommend the movie despite that.

In 1993, the IRA member Collette (Andrea Riseborough) is arrested in the London tube after leaving a bomb in the facility. MI-5 Agent Mac (Clive Owen) offers a deal to Collette to become an informer. She accepts the agreement to protect her son and in return Mac offers a new identity to her after a period working for the MI-5. Soon Mac learns that his superior Kate Fletcher (Gillian Anderson) is using Collette to protect her mole inside the Irish organization. Mac tries to find the identity of the informer and protect Collette.

"Shadow Dancer" is a dramatic thriller developed in slow-pace with a good story and a confused screenplay. The situation of Collette is heartbreaking since she has to betray family and friends to protect her son. The performances are top-notch, but there are ellipsis (or cuts in the edition) that are confusing. For example, I did not understand why Collette kisses Mac. My vote is six.

Title (Brazil): "Agente C – Dupla Identidade" ("Agent C – Double Identity")