In the film, she plays the Mary of the title, an almost obnoxiously wealthy woman living in Virginia, married to
Bruce Wayne Frank Grillo, an entrepreneur, with her own design business (the house they live in looks like it was ripped from the pages of Architectural Digest) and the doting mother to her somewhat withdrawn pre-teen son, George (Lux Haney-Jardine). Why is he so distant? It turns out he's being bullied at school, and when school officials won't really do anything, and her own (embarrassing) intervention doesn't work either, she packs up George and heads to South Africa for a six-month sojourn. There, she'll home school him and he'll be able to get his confidence back.
Meanwhile, in the U.K., Martha (Brenda Blethyn) watches her only son Joe (played with great charisma by Sam Claflin), a young twenty-something who wants to see the world, prepare as he heads to Mozambique to volunteer and work and spend time meeting people new people. Joe is getting ready to leave the nest, and while Martha continues to fuss over him just as she would if he were a child, she has to say goodbye anyway as he heads off on an adventure. But as you can already guess from the title, it won't be long until Martha meets Mary, but what will unite them?
The answer to that question is: death and coincidence. First, we see George die somewhat horrifically, with a mosquito bite that turns into malaria that turns into convulsions in the ER with the doctors unable to save Mary's son's life. After the funeral, Mary heads back to South Africa to seek some closure and just happens to coincidentally run into Martha at a fairly random beach, and after literally two minutes of conversation, they both realize they've lost their sons! No way! An instant and unbreakable bond is forged and before you can say "contrived" the two are doing everything they can to help the underprivileged and raise awareness about the preventable disease that claims too many lives, including children. Admirable intentions, right?
Bongo Mbutuma plays Mary's driver on her trips to South Africa, but there is little to define him other than he prefers country and western music over Ladysmith Black Mambazo (something that nearly knocks over Mary in astonishment, because of course, all African people should only listen to African artists, being the implication). Meanwhile, Joe's brief love interest is little more than a beautiful woman on his arm before he dies off screen (a curious decision given how central he is in the early stages of the movie, and one that perhaps suggests some material was left on the cutting room floor). But mostly, "Mary and Martha" presents a very exoticized Africa, where almost everything that's not the North American norm is positively kooky. And there's no shortage of adorable children to lens either...until a handful of them die in some particularly crass narrative and emotional manipulation.
Instead, "Mary and Martha" presents noble crusaders whose efforts wind up mostly redeeming themselves. The film's big climax comes at an Appropriations Committee hearing, where the government decides on how much aid they'll give to various charitable causes. As you might expect there are a lot of monologues, and pictures of cute African children shown and tears and the end result? Mary saves her marriage and rekindles her relationship with her distant father (Woods), who called in a political favor that allowed her to speak at the hearing. Martha...well, Martha gets to hang around and continue not going back to the U.K. to face the life she left behind. And the children, women and men still dying? They get the dignity of a pre-credits title card announcing that malaria can be ended in our lifetime if the commitment is there. [D]