Continuity mistake: When K and J drive to the bowling alley, the same junction with a shiny blue car and a man wearing an orange shirt is seen three times through J's window.
Continuity mistake: At the bowling alley, after K polishes the alien's head, the way his hair is messed up changes between shots.
Continuity mistake: When K questions J at the headquarters, K grabs his tie. From the immediate angle his hand is lowered.
Visible crew/equipment: After J arrives in 1969 and stands on the sidewalk at the Empire State Building, look at the doors behind him. As they close and open, the lighting rigs are reflected.
Continuity mistake: As J flies backwards after the fish creature sneezes, he breaks through the plate glass window, and has the bottles in his hands. After the cut, he's just breaking the glass, and the bottles are missing from his hands.
Continuity mistake: When J is shown the time-jump gear, the box is to the left of a pair of earphones and just an inch away from the log journal in front. When the shot changes the earphones are between both.
Continuity mistake: When Obadiah stands on the Chrysler building terrace his hair is either loose or tucked behind his ear.
Visible crew/equipment: As K opens the door to the Cosmic Bowl bowling alley, the camera crew and equipment is reflected in it.
Chosen answer: The gold saucer crashed in middle of the street was the ship Boris stole to get to earth. While they are in the restaurant Kay gets a call that tells him a ship was taken from lunar max and it was Boris who took it.