The “Core Four,” an affectionate nickname viewers have dubbed top-billed stars Tamara Tunie (Anita Dupree), Clifton Davis (Vernon Dupree), Karla Mosley (Dani Dupree) and Daphnée Duplaix (Dr. Nicole Dupree), are the undeniable pulse of CBS soap opera “Beyond the Gates.”

Any scene featuring a combination of these heavyweights is a treat, and the week of Mar. 23, was a masterclass in ensemble acting.

As the Dupree family grappled with Anita Dupree’s cancer battle, the matriarch hit a breaking point that took viewers through an exhausting, yet beautiful range of emotions.

Sister, Sister

The chemistry between the Dupree sisters always shines. Of all the sibling dynamics on the soap, theirs feels the most lived-in. It’s far from perfect, as Nicole Dupree’s judgmental streak sometimes clashes with Dani Dupree’s chaotic energy, but their “tough love” feels earned.

Before the heavy drama hit, we got a taste of their classic rapport: Dani Dupree teasing her older sister about her “situationships” while the renowned psychiatrist grilled her “wild-child” sister over lingering feelings for her ex-husband, Bill Hamilton (Timon Kyle Durrett).

Mosley and Duplaix share a natural shorthand that never feels forced. As someone with four sisters myself, the relatability is off the charts.

Watching them have girl talks about their exes, gush about their current partners and show deep concern for their parents feels like a private window into a real family’s living room.

A Masterclass in Pain

While the Dupree matriarch and patriarch have shared a string of emotional moments since the diagnosis, last week hit differently. The audience saw a side of Anita Dupree that we rarely see: vulnerable and physically depleted.

Tunie’s performance was visceral—appearing pale in her headscarf and loungewear. She used heavy breathing and subtle winces to convey a deep exhaustion.

When she flinched at her husband’s attempt to massage her hand with lotion, you could practically feel her nerve endings firing.

The conflict over the EGOT winner’s decision to forego treatment was beautifully played. Davis perfectly captured the retired senator’s desperation, particularly with the gut-wrenching line, “How dare you fix your face to say that to me.”

However, because of Tunie’s nuanced portrayal of Anita Dupree’s pain, viewers could actually sympathize with her desire to quit. For a woman who has always been in charge, choosing how her story ends was her final play for control.

Fighting Dirty for Family

When the Dupree sisters arrived to back their father at the hospital, they pulled out the ultimate “cheat code,” using Dupree grandchildren and great-grandchildren to convince their mother to get back into the fight and not sign a Do Not Resuscitate order. It was a “dirty” tactic, as Anita Dupree described it, but a necessary one.

While we’re used to Mosley’s powerful, outspoken performances, the real treat was seeing Duplaix break Nicole Dupree’s stoic, reserved exterior. The psychiatrist declared that her mother’s desire to stop her chemotherapy wasn’t a part of their agreement, so she wouldn’t carry out The Articulettes lead singer’s wishes.

Dr. Dupree is usually an anchor for the influential family, so seeing her crack under the weight of sorrow and relief in that hospital room was a compelling and striking moment.

The Core Four are the heart of this show, set in the exclusive Fairmont Crest. Their performances are so seamless that it’s easy to forget they’ve only been a TV family for a little over a year.

If last week proved anything, it’s that as long as the Duprees are together and centered, “Beyond the Gates” is required viewing.

“Beyond the Gates” airs on CBS at 2 p.m. EST Monday through Friday.