Reading Liz Moore’s delightful new novel, Heft, can remind one of that popular quote from Anna Karenina: “Happy families are all alike; every unhappy family is unhappy in its own way.”

Arthur Opp used to have a family once, but he doesn’t any more. He used to be a successful professor once, but he isn’t any more. Instead he is a dangerously obese (close to 500 pounds) academic who hasn’t stepped outside his crumbling Brooklyn home in close to ten years. Thanks to online shopping, he gets groceries delivered home and is so huge that he can’t even climb the stairs in his own house, let alone take a walk outside.

The only breath of fresh air in Arthur’s life is Charlene Turner, an ex-student with whom Arthur found much in common. “I recognized myself in her—in her awkwardness, her loneliness, her being very out of place, an outsider in a room full of compatriots. These feelings I recognized as my own,” Opp later narrates when describing first seeing her in his classes. Charlene, coming from broken circumstances herself, is desperate for a hero. She finds one in the college-educated professor Opp, and even though she makes it through only one semester at school, she is forever drawn to the idea of college as the one life raft to save her from drowning. She strikes up a correspondence with Arthur, little knowing that it is precisely these letters that have sustained Arthur’s emotional needs for the past ten years.

As Arthur imagines Charlene’s life through her letters, he in turn doesn’t realize that she is not the sweet, shy student he once knew. She has morphed into an alcoholic, abandoned by a husband who might or might not be the father of her teenaged son, Kel Keller. Planning to commit suicide, Charlene tentatively sends Arthur a picture of her son, hoping to introduce the two to each other. She might be depressed, but Charlene knows that her son’s life needs ballast and is convinced Arthur is the only one she knows, who can deliver. Overjoyed yet worried at the prospect of a visit from Charlene, Arthur employs a cleaning service to clear out years of clutter from his home. It is how he meets yet another lost soul, Yolanda, who soon becomes a fixture in Arthur’s life.

Eventually Charlene commits suicide and never does show up. Before doing so, however, she sets in motion a chain of events, which just might bring Arthur and her son together.

The talented Liz Moore narrates the story through chapters alternately told by Arthur Opp and Charlene’s son, Kel. Kel’s awkward plod through adolescence mirrors much of the anxiety Arthur feels toward life in general, and Moore does a great job at subtly pointing out the similarities between the two lost souls plodding along on parallel tracks.

This is also a story of the profound sense of unmooring that accompanies parental abandonment. Arthur’s eating habit, developed as a teenager, makes him the size he eventually becomes. This habit masks a painful past where a rich father abandoned him and moved to England. Kel Keller, too, is haunted by a deep sense of abandonment—first by his father, from whom he is sure he inherited a love of baseball, and then by his mother, Charlene. “Fathers aren’t all they are cracked up to be,” Arthur says once, and comforts himself: “I think it is possible to look at things differently: I believe we can choose to surround ourselves with a circle of people we love and admire & they can become our adopted family.”

One of the many strengths of Heft is that the characters never come across as mere “down-on-their luck” caricatures. What makes Moore’s book so uplifting is the sunny optimism that pervades even the darkest moments. Arthur has everything going against him, yet he never manages to completely lose hope. It doesn’t take much to make him happy. Even in his loneliness, Arthur can find a kinship, “a connectedness among the world’s lonely that I could turn to when I was very low. There was a delicious romance in being utterly alone, & I told myself I was nobler for it, & that there was a purpose to my solitude.” There are times though when this same optimism can get blinding—a case of “too much of a good thing.”

Liz Moore’s novel eventually is a winner because it shows us that hope can be a powerful vehicle; that even the loneliest of souls can find a way out of the darkness. The message she conveys in her new novel is full of, well, heft.