Two new Off-Broadway plays focus on characters encountering conflict, angst and passion as they pursue their creative ends. Scene Partners by John Caswell, Jr. at the Vineyard Theater blurs the lines between reality and cinematic fantasy while David Adjmi’s Stereophonic at Playwright Horizons takes an almost documentary-like approach to the painstaking journey of creating a rock album. Both are fascinating and gripping depictions of the creative process and how movies and music reveal the inner struggles of their creators.

As he did in his previous work Wet Brain, which ran at Playwrights last summer, Caswell mixes a believable situation with the fantasies of his characters to create a weird, dream-like world. In Wet Brain, it was a family dealing with the father’s alcoholism and descent into madness fused with allusions to sci-fi and outer-space aliens. In Scene Partners, we follow the bizarre journey of 75-year-old, recently widowed, aspiring actress Meryl Kowalski (the luminous Dianne Wiest) as she leaves her home in the Midwest for 1985 Hollywood and film stardom. Within a matter of days, she acquires an agent (at gunpoint), a spot in a hot acting class, and an audition for a self-written movie based on her own life in which she hopes to play the leading role.

The scenes are exaggerated and unreal, so we don’t know which are actual and which are figments of her possible dementia. Meryl often appears to be playing out scenes from her favorite films as she compares her brutal dead husband to Stanley Kowalski in Streetcar and connects with her drug-addicted daughter during an out-of-body experience while getting an MRI scan. Meryl’s real sojourn seems to be one of self-discovery. Her autobiographical screenplay exposes a sexual assault from her stepfather and an adult life of despair and poverty.

But it’s hard to connect with Meryl since Caswell’s text never reveals what’s real and what’s not. Even her train trip to LA is combined with scenes from Doctor Zhivago and her early days in LaLa Land are depicted like a film noir. Her name evokes comparisons to the great Streep who was emerging as the star of stars at the time of the play. Almost the entire play could be in Meryl’s head since we also see her getting numerous medical examinations at the insistence of her sister (the subtle Johann Day) with whom she is staying. Despite the confusing nature of the script, Scene Partners offers a touching depiction of a woman seeking meaning for her seemingly random, empty life.

The brilliantly imaginative director Rachel Chavkin gives this confusing yet moving work the best possible production, fluidly staging the scenes with the aid of David Zinn’s set of mobile panels displaying evocative projections of old films. (Anne Troup is listed as video producer.) Wiest brilliantly commands the stage as Meryl, searching for a purpose in a maze of movie memories and holding on to her sanity with a fierce grip. In addition to the sweetly supportive Day, Josh Hamilton, Eric Berryman, Carmen M. Herilhy and Kristen Sieh shine in multiple roles.

If Scene Partners is the fever dream of a movie fan desperate for acceptance and fulfillment, Stereophonic is a brutal reality check and harsh reminder of the cost of fame. Set in two different, equally claustrophobic recording studios in the late 1970s (David Zinn—again—designed the accurate period setting), this finely detailed work follows the ardurous creation of an album from a Fleetwood Mac-like group as their relationships shift and finally break apart under the pressure of producing a Billboard chart climber. Adjmi’s dialogue, the realistic acting and Daniel Aukin’s seamless direction are so naturalistic, it feels like we’re spying on these volatile creatives.

When lead singer and songwriter Diana’s single from their previous album becomes a hit, it causes jealous friction from her boyfriend Peter, the lead guitarist and demanding head of the group who senses she is the real talent of the company. British married couple Reg (bass guitar) and Holly (keyboards and vocals) are constantly bickering over Reg’s excessive alcohol and drug abuse, while drummer Simon is conflicted between his ambition to manage the group and missing his wife and children back in England. Meanwhile, engineer Grover and his assistant Charlie frantically attempt to keep up with the constant changes in tempo, volume, and temperament. By the time the album is completed, both couples have split, Diana is on her way up, Grover has been promoted to producer, and the artists are left questioning their values and relationships.

The seven-member ensemble are so integrated into Adjmi’s material and Will Butler’s rapturous, yearning rock songs, it’s hard to single anyone out. Sarah Pidgeon perfectly conveys Diana’s insecurities and self-deprecation even as she beautifully performs the tender ache in a series of rock ballads. Juliana Canfield captures Holly’s strength and perceptiveness, particularly in a strangely moving monologue describing the character’s favorite film, Don’t Look Now. Tom Pecinka balances Peter’s driven and obnoxious perfectionism with a gnawing vulnerability. Chris Stack does an equally fine job of combining Simon’s ambition and his domestic impulses. Will Brill is brilliantly funny as the stoned Reg as are Eli Gelb and Andrew R. Butler as the harried Grover and Charlie.

Stereophonic is like a Robert Altman film in the seemingly unstudied, relaxed way it depicts the musicians’ clashes and struggles and how they pour them into their work. The three-hour running time zooms by. Kudos also to Enver Chakartash’s period costumes and Ryan Rumery’s sensitive sound design, capturing ever aural nuance of the songs as their creation and execution is dramatized.

Scene Partners: Nov. 15— Dec. 17. Vineyard Theater, 108 E. 15th St., NYC. Running time: 90 mins. with no intermission. vineyardtheatre.org.

Stereophonic: Oct. 29—Dec. 17. Playwrights Horizons, 416 W. 42nd St., NYC. Running time: three hours including intermission. playwrightshorizons.org.