Sam and Gibby operate a secret restaurant in the basement at school. Elsewhere, Spencer creates a security robot, which develops a glitch.
Carly and her pals commemorate "iHalfoween," but they don't appreciate Nevel's prank on them.
Sam becomes Freddie's coworker and ruins his enjoyment of the job. Elsewhere, Carly struggles to score a date with a clueless guy; and Spencer does volunteer work at a fire station.
Spencer encounters Chuck's little brother and discovers he's a bigger terror than Chuck. Elsewhere, Freddie repairs Gibby's phaser, making the toy more dangerous than he intended.
Carly doesn't allow T-Bo in the loft, so he prohibits her from entering the Groovy Smoothie. Elsewhere, Freddie and Gibby experience the upside of being in a band.
Carly and her pals want Spencer to make some new friends who are the same age as him, and they find some potential candidates.
Carly gets in trouble when she ignores Sam's warning about a pal who was recently released from a juvenile-detention facility. Meanwhile, Spencer has fun with a pair of night-vision goggles.
Sam's mother gets arrested in Las Vegas, so the gang head there to pawn their valuables and post her bail.
The gang search for the bandit who snatched Sam's laptop. Meanwhile, Spencer needs a child companion to visit an arcade, so he happily volunteers to babysit Guppy.
In the series finale, Carly hopes her father will make a trip home to escort her to a big dance, but when he's unable to do it, an ill Spencer tries to fill in for him. Elsewhere, Sam rebuilds a motorcycle; and Freddie obtains a new phone.