Fall TV Preview: 'Welcome to the Family'

NBC's new comedy series Welcome to the Family is anything but a cordial invitation for two families to meet. The cast gave ET the scoop on the new show and teased the comedy that occurs when two very different families are forced to interact.

"Molly Yoder" (Ella Rae Peck) and "Junior Hernandez" (Joseph Haro) are two high school seniors who have varying personalities but have found an attraction for each other. The two keep their relationship hush-hush, but then are forced to reveal their relationship when they discover a life-changing bit of information.

Molly is pregnant.

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This revelation catches both of their families off-guard and forces their parents, who lead different lives and embrace different philosophies, to blend for the sake of their children.

"I get Molly Yoder pregnant and that's...what brings these two families together," Haro laid out the premise of the show. "We have to come clean and have to confess and then deal with this wonderful new baby that we're about to have."

While the families are technically meeting for the first time when their children reveal the important news, there is a bit of history that exists between the two fathers (portrayed by Mike O'Malley and Ricardo Chavira) that causes them to further butt heads.

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"They drop that bomb on both families as they get the families together for the first time shortly after the graduation. Unbeknownst to the two children, the fathers have coincidentally met previous to this announcement and do not like each other," previewed Chavira, who plays "Miguel Hernandez." "Comedy ensues."

Although the mothers haven't had any previous encounters, their innate differences put them at odds as well. They aren't as fervently heated as their spouses, but Hernandez matriarch "Lisette" (Justina Machado) says they still clash.

"We hope to not get along so well. We definitely want to have some conflict because it's going to give us something to do," Machado said. "We don't want to be the typical sitcom wives that just stand back and let the men do all the stuff and we just sit there."

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Watch the video above for a preview of Welcome to the Family with Machado, Haro, Chavira, Ella Rea Peck, and Mary McCormack.

The show premieres October 3 at 8:30 p.m. on NBC.