Johnny Galecki Makes His First Appearance on 'The Conners' -- And Drops Two Major Bombshells

The 'Big Bang Theory' star reprised his role as David on the 'Roseanne' spinoff on Tuesday.

Warning: Spoiler alert! Do not proceed if you have not watched Tuesday's new episode of the Roseanne spinoff, The Conners. Read ET's complete guide of Roseanne Barr's fallout, from the cancellation of Roseanne to the creation of The Conners.

Johnny Galecki made his first appearance on The Conners on Tuesday -- and his character, David, had a few bombshells to drop!

Darlene's estranged husband dropped by the Roseanne spinoff this week, bringing along his new girlfriend and "soulmate," Blue (Juliette Lewis), who immediately butted heads with his ex. However, the pair shared a nice moment together when reminiscing about Darlene's mom, Roseanne (Roseanne Barr), who was revealed to be dead of an opioid overdose in last week's season premiere.

"It's so strange being in this house without your mom," David told Darlene (Sara Gilbert). "When you and I were having problems, she'd always take me aside and say, 'David, I can't understand you when you're crying.'"

"Well, you were the daughter she always wanted," she replied with a laugh.

But the episode turned out to be more about the pair moving on from each other than reminiscing about old times. After David and Darlene got in a fight over their daughter, Harris (Emma Kenney), sneaking a boy into David's house during a weekend visit and losing her virginity -- and talking to Blue about it before she told her mom -- Darlene revealed that she was ready to make their split permanent.

"It's clear that things are serious with you and Blue, so I think it's time we get a divorce," she said tearfully, before also admitting that she had met a handsome stranger (Justin Long) at the bar the other night, and went on a date with him.

David agreed that it made sense, but added, "It's gonna be weird not being married to you."

"I would have thought it got weird when you started living with another woman," Darlene shot back, before admitting, "It's gonna be weird not being married to you too."

ET recently spoke with Lewis about joining The Conners' TV family and being partnered up with a familiar face in Galecki -- the pair starred together as siblings in 1989's National Lampoon's Christmas Vacation

"I could not believe how homey it felt on set and just comfortable," she raved, "and I couldn't believe they asked me to be a part of it."

The Conners premiered last week and addressed the absence of Barr, following Roseanne's cancellation in May over Barr's racist tweets. After it was revealed that Barr's character had been killed off due to an accidental overdose, the comedian released a statement slamming the episode, explaining that the decision to have her die from drug abuse "lent an unnecessary grim and morbid dimension to an otherwise happy family show."

After the episode aired, star Lecy Goranson told ET: "I don't know what show that she's referring to but I've never seen our show as a happy family show. I think our show is funny, I think that it's real, I think that everyone who's on the show and a part of the show has a vested interest in it being grounded and for it to resonate, I just don't see it as a happy family show." 

See more from The Conners' return -- and Lewis' debut on the show -- in the video below.

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