The Addams Family 2 (2021)

At a science fair, Wednesday Addams is set to present her experiment, where she uses her pet octopus Socrates' DNA on Uncle Fester to show how humans can be improved (with the side effect of gradually transmutating Fester). However, she is dismayed when she sees her family arrive. Nonetheless, her work gets noticed by scientist Cyrus Strange. Back at the Addams' home, Gomez worries that the children are drifting apart from him and Morticia, so he decides to take them on a family vacation. Before the family, Fester, Thing and Lurch head on a road trip across the United States, Gomez and Morticia are approached by a lawyer named Mr. Mustela, who claims that Wednesday was switched at birth and may not actually be an Addams, but they ignore him. On the road, the Addams family is pursued by Mustela and his employer's henchman Pongo.

The family is initially set on going to Salem, Massachusetts, but Fester, who is slowly mutating due to the experiment, ends up making a detour to Niagara Falls. The family later stops in Sleepy Hollow, New York. Gomez and Morticia bring up Mustela and his claims about Wednesday, so Fester mentions a story when he visited Wednesday the day she was born and juggled babies in the delivery room. This only worsens Gomez and Morticia's fears that Wednesday may not be their biological child, which Wednesday overhears.

Gomez brings everyone to Miami to get in touch with Cousin Itt, in hopes he can help with their current dilemma. Itt joins them on the trip as they pass through San Antonio and leaves the family early at the Grand Canyon. Meanwhile, Wednesday traps Mustela in a rope trap on her own and learns he is working for Cyrus before "letting him go". Cyrus suggests to Wednesday that he is her true father and invites her to his home in Sausalito, California. Wednesday runs a DNA test using Gomez's hair, which seemingly proves that she is not his daughter. Wednesday leaves the family while they sleep, but Lurch catches up with her. The rest of the Addams learn where she is heading and follow suit.

At his home, Cyrus shows Wednesday a formula he developed to make human–animal hybrids, similar to Wednesday's experiment. When the rest of the Addams family shows up, Wednesday is persuaded to stay with Cyrus. After Pugsley finds out that Cyrus' daughter Ophelia is a pig, Cyrus reveals he is using Wednesday, as her formula was better than his. He captures the family to test on them, but Wednesday refuses to do so. Cyrus tries to get Pongo to go after her, but it is revealed Lurch and Pongo knew each other before while in a mental asylum and they decide to free the Addams. Cyrus comes into contact with his formula during the scuffle and turns into a hybrid chicken-cow-goat-pig monster. Disgusted by Wednesday's compassion, Cyrus admits that the DNA results were fake and Wednesday is not his daughter. Feeling that Wednesday is no longer any use to him, Cyrus tries to kill the family, but is stopped by Fester who has fully mutated into an octopus monster. After the two fight, Cyrus falls off a cliff onto a marriage proposal. Fester is turned back to normal by Wednesday using a necklace given to her by Morticia that contains the family's blood.

Wednesday reunites with her family and they return home along with Pongo and Ophelia, the latter of whom has become fully human following contact with Wednesday's formula and falls in love with Pugsley. Gomez then reveals to Wednesday that he has worn a toupée ever since he lost his real hair in a napalm accident. He promises the family that next time, he will take them on a trip across the world.