“Viper Club” is an attempt at a very difficult balancing act. It doesn’t quite succeed, but it deploys enough persuasive elements to make the attempt involving.

As directed by Maryam Keshavarz (who also co-wrote with Jonathan Mastro), “Viper Club” wants to be faithful to the wrenching reality of a real-world phenomenon, the kidnapping for ransom of freelance journalists in conflict zones like the Middle East.

Though criticized by Diane Foley, mother of James Foley, a young journalist who was killed in 2014, “Viper Club” takes its mandate seriously for shining a light on this disturbing situation.

But “Viper Club” also wants to be regarded as emotional drama and character study — as the choice of Susan Sarandon as its star indicates. It manages to keep all these balls in the air for a while, but it’s not finally as involving as it might have been.

Sarandon, a proficient actress whose approach to character is not always restrained, has seized the opportunity of playing the lead here and responded accordingly, appearing in just about every scene and keeping her work sharply focused.

The actress plays Helen Sterling, a veteran emergency room nurse in an upstate New York hospital whose son, a freelance video journalist named Andy (Julian Morris), has been seized by terrorists in an unnamed part of the Middle East and offered for the preposterous ransom of $20 million.

Helen is encountered several weeks into the ransom situation, having told no one and barely holding it together at the hospital where both a new doctor from Iran (Amir Malaklou) and her supervisor (an excellent Adepero Oduye) count on her.

Whenever she can get away, Helen takes an overnight bus to visit the FBI and the State Department (which do not communicate with one another) to find out what they’re doing to free her son.

What both entities tell her sounds based on the reality: It’s best to take things slowly with terrorist organizations. There is a science to negotiating. Paying ransom is illegal. You just have to trust the process. Helen is beyond frustrated, but she feels she has no choice.

Then, Andy’s ex-girlfriend Sheila (Shelia Vand) shows up. Also a journalist, she tells Helen about Viper Club, an online network where resources both informational and fiscal are pooled for people who need help with this kind of situation.

That tip leads Helen to Charlotte (Edie Falco), a wealthy New Yorker whose son was similarly taken but ransomed back. She, with Andy’s good friend Sam (Matt Bomer), think Helen should go public with her plight to raise whatever it takes to free her son.

“Viper Club” is expert at showing Helen’s dilemma, at underscoring how difficult it is for this ordinary person who exercises to Richard Simmons videos to figure out which side knows what it’s doing, which side she should trust.

One of “Viper Club’s” other focuses is on the nature of Helen’s relationship with her son, and considerable time is given to flashback memories of times they have spent together over the years.

Initially, this is a strength, adding texture to the film’s narrative, but the flashbacks start to feel repetitive, and the emphasis on motherhood, though hard to argue with, is not particularly dramatic.

Similarly, a parallel hospital-based story of a mother who has to make a crucial decision about a daughter in a coma begins strongly but ends up too obvious a parallel to the main story to be effective.

Though its subject matter ensures that “Viper Club” has any number of strong dramatic moments, it too often feels like it’s marking time. While the reality that inspired its story is shocking and disturbing, the resulting film finally is not.

“VIPER CLUB”

** 1/2

(R, 1:49)