Threatened by a doctor's kindness toward Tammy, Mark tries to get her an exotic animal, only to have his face ripped off by the newly purchased chimpanzee. Meanwhile, Hank bonds with the chimpanzee via its bluetooth, and David's dog saves David and Mernft Man from a pet snake.
When David, Andrea, Mark, and Tammy go on a cruise together, David and Andrea unexpectedly rekindle their romance. Mark's preoccupation with reeling in a big fish to outcompete Steve DelVecchio leads to him catching a whale that jeopardizes the safety of the entire cruise. Meanwhile, Hank goes on a date with a mermaid that goes awry when she reveals her distaste for hot dogs.
Mark, in an attempt to bond with his stepson Darren, insists on teaching him how to throw a handmade boomerang that was gifted to Darren by his father. The two soon find themselves on a trek deep into the Jersey woods in search of it, where they encounter the Jersey Devil himself. Meanwhile, David is the recipient of a sex doll that he swears he didn't order, and is put through the wringer trying to return it.
When Tammy is upset that an elite country club only takes men, Mark joins it to supposedly change things from within; Tammy's passion for the club infuriates the owner's wife, Ellen; Mark's entry into the club ruins the natural order.
Jealous of the attention Tammy gets for saving the life of a choking stranger, Mark buys a Jaws of Life to efficiently save lives; Tammy's life is threatened when she rejects the advances of Paul, the stranger she saved.
Mark buys himself a Superbowl ring and leverages it to get special treatment at the Eagles game; Hank has an adventure with cutting-edge mascot technology.
Mark puts his piloting skills to the test.
Mark, Tammy, Hank, and Darren discover a magical, immersive, Jumani-style board game where they have to overcome their interpersonal differences in order to survive. David, facing the most important deadline and worst writer's block of his career, seeks solitude.
Mark, trying to prove to Tammy that he can get babies to like him, writes a hit song that becomes the next Baby Shark. He enlists his family and neighbors to join his management team, putting these relationships to the test during his meteoric rise and humiliating fall. Meanwhile, David tries to capitalize in Mark's wake by resuscitating his old and out of touch climate change educational magic act.
Mark throws his hat into the ring as an Ad Man after being shown up by a group of execs.
After feeling slighted by a Navy recruiter, Mark sets out to join an elite unit of the Marines, only to be thwarted by his inability to properly make a bed. David teams up with a Veteran, hoping to ghost write the next American Sniper and can no longer distinguish fantasy from reality as his subject reveals stories from his past that are stranger than fiction.
Mark accidentally murders Hank with a crossbow while hunting a deer.
Mark goes into business with Gary & Barry's Water Ice Shoppe, a Glantontown institution, when faced with being deprived of his favorite summer snack during their annual winter closure.