The Debt has received a slew of positive reviews, but some, on closer inspection, betray a secondary note of disappointment. After a summer when Hollywood brought us a record number of sequels, remakes and films whose heroes and conflicts were enhanced with digital wizardry, it’s hard not to harbor high expectations for a historical thriller starring Helen Mirren and directed by John Madden, of Shakespeare in Love fame. Finally, some weary moviegoers may surmise, a drama with no cowboys, aliens, wizards, robots, talking animals or superheroes, just good acting and a gripping, thought-provoking plot.

Well, sort of. The Debt has just enough of those elements to satisfy anyone jonesing for an “adult” thriller on the big screen. But its script doesn’t offer enough twists, turns or quandaries to make it a truly memorable entry in the genre. The first credit on that script goes to Matthew Vaughn, the writer-director of Kick-Ass and X-Men: First Class, and it shows. After a slow, effective buildup, The Debt goes for a fairly predictable, action-oriented denouement. It doesn’t go overboard on the ass kicking, but it doesn’t give all its thrills real-world weight, either.

Mirren plays Rachel Singer, a retired Mossad agent whose greatest achievement was hunting down a Josef Mengele-type Nazi doctor when she was just 25. Her grown daughter has published a book about the case, drawing Rachel’s two ex-partners, Stephan and David (Tom Wilkinson and Ciáran Hinds), to her launch party. While Rachel publicly accepts the laurels, her tense demeanor suggests that the trio’s 1965 mission didn’t unfold quite as the book tells it.

David’s abrupt suicide strengthens that suspicion — and moves the film into flashback mode. The Debt’s best scenes take place in blue-tinged, claustrophobic, Cold War-era East Berlin, where the young Rachel, David and Stephan (Jessica Chastain, Sam Worthington and Marton Csokas, respectively) use cunning to approach their prey (Jesper Christensen) in his postwar guise as a courtly gynecologist. Unluckily for Rachel, she’s the one qualified to get in the stirrups.

The cat-and-mouse game becomes two-sided when the wily old Nazi uses the young agents’ weaknesses against them. The script strongly hints that Rachel and David lost their parents to the camps, a trauma that left them volatile and vulnerable. But we never learn the details, nor do we come to know the agents beyond our first impressions of them: Stephan is flip and worldly, David distant and damaged, and Rachel eager to prove herself.

The young actors do their best with the limited material, and despite a distracting lack of resemblance to their older counterparts. (It doesn’t help at all that Hinds looks more like Csokas than like Worthington.) When we return to the present, and Mirren-as-Rachel faces her “debt,” the film should rise to a crescendo, fraught with revelations of the past. Instead, this is where it slopes toward conventional catching-a-bad-guy drama.

If this summer of not-great movies leaves us with anything worthwhile, it’s the rising star of Jessica Chastain. Somehow the previously obscure actress managed to be both affecting and convincing as a free-spirited Texan mother (The Tree of Life); a broadly comic trailer-trash gal made good (The Help); and a sensitive Israeli operative. She’s like the young Julia Roberts with range, and her emotional transparency compensates for The Debt’s lack of depth. Let’s hope she doesn’t end up headlining video-game adaptations.