What do people do when they have emotional pain? Sometimes it shows physically in stomach aches. Sometimes to release internal stress people risk physical injury doing wild stunts, like jumping off a school roof on a bike. In Rajiv Joseph’s humorous and profound Gruesome Playground Injuries, currently in revival at the Lucille Lortel Theater until December 28th, we meet Kayleen and Doug. Two-time Tony Award winner Kara Young and Succession star Nicolas Braun portray childhood friends who connect, lose track of each other and reconnect over a thirty year period.

Joseph charts their growth and development from childhood to thirty-somethings against a backdrop of hospital rooms, ERs, medical facilities and the school nurse’s office, where they initially meet when they go to seek relief from their suffering. After the first session when they are 8-year-olds, to the last time we see them at 38-year-olds at an ice rink, we calculate their love and concern for each other, while they share memories of the most surprising and weird times together. One example is when they stare at their melded vomit swishing around in a wastepaper basket when they were 13-year-olds.

How do they maintain their relationship if they don’t see each other for years after high school? Their friends keep them updated so they can meet up and provide support. From their childhood days they’ve intimately bonded by playing “show and tell,” swapping stories about their external wounds, which Joseph implies are the physical manifestations of their soul pain. After Doug graduates from college, when Doug is injured, someone tips off Kayleen who comes to his side to “heal him,” something he believes she does and something she hopes she does, though she doesn’t feel worthy of its sanctity.

Joseph’s two-hander about these unlikely best friends alludes to their deep psychological and emotional isolation that contributes to their self-destructive impulses. Kayleen’s severe stomach pains and vomiting stems from her upbringing. For example in Kayleen’s relationship with her parents we learn her mother abandoned the family and ran off to be with other lovers while her father raised the kids and didn’t celebrate their birthdays. Yet, when her mother dies, the father tells Kayleen she was “a better woman than Kayleen would ever be.” There is no love lost between them.

Doug, whose mom says he is accident prone, uses his various injuries to draw in Kayleen because he feels close to her. She gives him attention and likes touching the wounds on his face, eyes, etc. Further examination reveals that Doug comes from a loving family, the opposite of Kayleen’s. Yet, he may be psychologically troubled because he risks his life needlessly. For example, after college, he stands on the roof of a building during a storm and is struck by lightening, which puts him in a coma. His behavior appears foolish or suicidal. Throughout their relationship Kayleen calls him stupid. The truth lies elsewhere.

Of course, when Kayleen hears he is in a coma (they are 28-year-olds), after the lightening episode, she comes to his rescue and lays hands on him and tells him not to die. He recovers but he never awakens when she prays over him. She doesn’t find out he’s alive until five years later when he visits her in a medical facility. There, she recuperates after she tried to cut out her stomach pain with a knife. She was high on drugs. At that point they are 33-year-olds. Doug tells her to keep in touch, and not let him drift away, which happened before.

Joseph charts their relationship through their emotional dynamic with each other which is difficult to access because of the haphazard structure of the play, listing ages and injuries before various scenes. In this Joseph mirrors the haphazard events of our lives which are difficult to figure out. Throughout the 8 brief, disordered, flashback scenes identified by projections on the backstage wall listing their ages (8, 23,13, 28, 18, 33, 23, 38) and references to Doug’s and Kayleen’s injuries, Joseph explores his characters’ chronological growth while indicating their emotional growth remains nearly the same, as when we first meet them at 8-years-old. In the script, despite their adult ages, Joseph refers to them as “kids.”

Toward the end of the play via flashback (when they are 18-year-olds), we discover their concern and love for for each other and inability to carry through with a complete and lasting union as boyfriend and girlfriend. When Doug tries to push it, Kayleen isn’t emotionally available. Likewise when Kayleen is ready to move into something more (they are 38-year-olds), Doug refuses her touch. By then he has completely wrecked himself physically and can only work his job at the ice rink sitting on the Zamboni.

Young and Braun are terrific. Their nuanced performances create their characters’ relationship dynamic with spot-on authenticity. Acutely directed by Neil Pepe, we gradually put the pieces together as the mystery unfolds about these two. We understand Kayleen insults Doug as a defense mechanism, yet is attracted to his self-destructive nature with which she identifies. We “get” his protection of her because of her abusive father. One guy in school who Doug fights when the kid calls her a “skank,” beats him up. Doug knows he can’t win the fight, but he defends Kayleen’s name and reputation.

The lack of chronology makes the emotional resonance and causation of the characters’ behavior more difficult to glean. One must ride the portrayals of Young and Braun with rapt attention or you will miss many of Joseph’s themes about pain, suffering and the salve for it in companionship, honesty and love.

In additional clues to their character’s isolation, Young and Braun move the minimal props, the hospital beds, the bedding. They rearrange them for each scene. On either side of the stage in a dimly lit space (lighting by Japhy Weideman), Young and Braun quickly fix their hair and don different costumes (Sarah Laux’s costume design), and apply blood and injury-related makeup (Brian Strumwasser’s makeup design). In these transitions, which also reveal passages of time in ten and fifteen year intervals, we understand that they are alone, within themselves, without help from anyone. This further provides clues to the depths of Joseph’s portrait of Kayleen and Doug, which the actors convey with poignance, humor and heartbreak.

Gruesome Playground Injuries runs 1 hour 30 minutes with no intermission through 28 December at the Lucille Lortel Theater; gruesomeplaygroundinjuries.com.