P.J. Peavy, left, Susan Cookie Baker, ToReeNee Wolf, and Geri Hooper Wharham play decades-long friends in the Invisible Theatre’s “20th Century Blues.”

Laughter, anger, tears and tenderness fill the stage when four women, friends for 40 years, reflect on changes brought by time, age and circumstances in Invisible Theatre’s production of Susan Miller’s “20th Century Blues.”

The play’s premise is contrived but it has a genuine and sincere feel.

The eclectic quartet met in jail after a protest in the ’70s.

It was a time when “you were no one if you didn’t spend a night in jail.”

Danny (Geri Hooper Wharham) takes a behind-the-bars photograph and a tradition develops. She continues to photograph the group — real estate agent Sil (P.J. Peavy), investigative newspaper journalist Mac (ToReeNee Wolf) and veterinarian Gabby (Susan Cookie Baker) — every year for four decades.

The relationships are challenged when Danny is offered a TED (technology, entertainment, design) Talk and a retrospective show in New York’s Museum of Modern Art. At the 40th and final photo shoot, Danny asks her pals to sign waivers so she can exhibit the collection and show the images during the TED Talk.

Expectations, disappointments and raw emotions bubble up.

No one has seen the photographs — not even the subjects. The women are not sure they want their lives exposed. They are fearful of the private becoming public.

Sil, planning a facelift for a more youthful look she feels is necessary to be effective in the competitive New York real estate market, calls the photo array “40 years of gradual decline.” Mac fears the attention might stir up something from past news coverage.

Punctuated with snappy one-liners, the women reminisce about their lives, children, sex, gender issues, divorces, the demise of print journalism, anti-depressants, AARP magazine and the impact of terrible events, like the John F. Kennedy assassination.

They struggle to remember just the right word — we’ve all done that, right? — and dance to Aretha Franklin’s “Respect.”

The four actors make most of the dialogue feel genuine, like conversation or a squabble.

Peavy’s Sil has an edge and wariness and lets the audience understand Sil’s drive to be successful.

Baker gives Gabby vulnerability. Carrying her knitting in a Lululemon bag and wearing adorable dog-print leggings, Gabby is staying in a hotel because she is “training for widowhood.” Her husband’s health is fine, but she fears she will be left alone.

Wolf is powerful as a gay, black woman who sees her career in investigative journalism being tossed away. And Wharham is grounded, composed and loving as photographer Danny.

Added to the mix, Molly McKasson as Bess, Danny’s 91-year-old mom, and Cole Potwardowski as Danny’s millennial, techie son, offer fresh perspectives from both ends of the age spectrum.

Director Susan Claassen and assistant director Fred Rodriguez keep the actors comfortably moving and the discussion flowing in the stage set as the living and kitchen areas of Danny’s New York apartment.

However, at times some of the actors were positioned so their heads turned too far away from the audience and toward the other actors, which muffled the dialogue for the audience.

There were a few stammers and tongue-tied deliveries on opening night, April 24, which could have been opening-night jitters or keeping up with the quick pacing.

From Gabby’s flowing top and funky boots, to Danny’s practical slacks and artsy scarf, costume designer Maryann Tombino expressed the characters’ inner spirit through their clothing.

“20th Century Blues ” is a comedy about aging and friendship that has heart. It is sweet, but you won’t need a sugar detox.

Ann Brown is a former reporter and editor for the Star.