Brittany Runs a Marathon

Brittany Forgler is a 28-year-old living in New York City with her roommate Gretchen, a teacher's assistant dreaming of social media fame. Employed as a greeter at an off-Broadway theater, Brittany is a hard partier, overweight, and abuses Adderall. Visiting a new doctor to score a prescription, she receives unwelcome news; she must get healthy and lose weight. She visits a nearby gym only to find even the cheapest fee is out of her reach. Despite her fear, she tries running for the first time, successfully running one block. She is invited to run in a group with her neighbor Catherine, whom Brittany detests for her seemingly perfect life. Sucked into another night of partying by Gretchen, Brittany arrives for the group run and meets Seth, another struggling runner, learning they have equal goals. Brittany, Seth, and Catherine bond and, after a 5K run, set the ultimate goal: running in the New York City Marathon.

Interviewing for a live-in nanny position, Brittany instead gets a second job as a pet sitter. On her first day, she meets fellow pet sitter Jern, who is essentially living in the house against the rules. After a falling out with Gretchen over her changing lifestyle, Brittany moves into the house as well, bonding with Jern over their stalled lives. Seth and Catherine's predictions that Brittany will have sex and fall in love with Jern eventually come true.

Brittany gets within five pounds of her goal of losing 45 pounds. Unable to win a place in the marathon through a lottery, as Seth does, her only hope is to raise enough money for a charity. At Catherine's divorce party, she informs Brittany that she often raises a lot of money for a favorite charity, and offers to have $5000 donated in her name so Brittany can run in the marathon. Brittany's pride, and continued reluctance to let Catherine into her life, force her to turn down the offer, and she leaves. She regains weight, forcing her to run even harder, until one of her shins becomes too painful to walk on. Five weeks from the marathon, her doctor informs her she has a stress fracture and will be unable to run for six to eight weeks.

Dejected, Brittany returns to the dog-sitting house and discusses the state of her life with Jern. The homeowners return and, disgusted Jern and Brittany have been living there, fire them. Brittany takes a bus to Philadelphia to visit her sister Cici and brother-in-law Demetrius, who was a father figure to Brittany after their parents' divorce and father's death. She ignores calls and texts from Catherine, Seth, and Jern, saddened to see Seth and Catherine with their marathon medals. That same day, she disrupts Demetrius's birthday party by making comments about an overweight female guest. After a stern but heartfelt talk with Demetrius, Brittany returns to New York and her former apartment, now alone as Gretchen is living with her on-and-off boyfriend Terrence. She applies for advertising jobs, for which she trained initially, and lands an entry-level position in Tribeca.

Catherine reveals that running was a distraction from her nasty divorce, explaining that years ago, she broke her wrist and was prescribed Oxycodone, which her husband did not believe she should have. He discovered she was taking it anyway, using that fact to deny her visitation rights to their children. Brittany encourages her to take small steps to win her children back, and sets boundaries with Jern to simply be friends.

One year later, Brittany runs in the marathon. At the 22-mile mark, she develops a cramp and has to pause. She rejects medical assistance, but accepts an assistant's offer to help her up. While considering quitting, she finds Seth, his husband and sons, and Catherine in the crowd cheering her on. She also encounters Jern, who says he loves her. She then keeps going, finishing the marathon.

An epilogue reveals Brittany and Jern living together as a couple, but she does not want to marry him despite his suggestion. She kisses him, and leaves the house to go on a run.

The story of Brittany was inspired by Colaizzo's roommate, Brittany O'Neill, who appears in photos before the end credits.[3]

In November 2017, it was announced Jillian Bell, Michaela Watkins, Utkarsh Ambudkar, Lil Rel Howery, Micah Stock and Alice Lee would star in the film, with Paul Downs Colaizzo directing from a screenplay he wrote. Tobey Maguire, Matthew Plouffe, Margot Hand, will serve as producers on the film, under their Material Pictures and Picture Films banners, respectively. Bell, Downs Colaizzo, and Richard Weinberg will serve as executive producers.[4] Jolian Blevins and Padraic Murphy served as co-producer and associate producer, respectively.[5]

It had its world premiere at the Sundance Film Festival on January 28, 2019.[8][9] Shortly after, Amazon Studios acquired worldwide distribution rights to the film for $14 million.[10] It was released on August 23, 2019.[11]

• Brittany Runs a Marathon on IMDb 
• Brittany Runs a Marathon at Rotten Tomatoes
• Brittany Runs a Marathon at Metacritic