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 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, 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.