Continuity mistake: In the scene when Jackie Chan gets out from underneath the cab his back is dirty. in the next shot when he goes in to the back seat of the cab to lay down his back is clean. (00:07:45)
Continuity mistake: During the scene when Mr. Devlin is in De L'Air, the bug store, the eyes of the young black woman with whom he is speaking change back and forth from blue-gray to brown. (00:15:18)
Continuity mistake: The back of Jennifer Love Hewitt's gown at the final party changes from when they are dancing when they arrive to when they are kicking butt in the lab.
Continuity mistake: When Jimmy was in a fight with the mean biker dude, the guy punches and shatters the driver's side window of Jimmy's taxi. After the fight, when Jimmy is driving a woman, the window is perfectly intact.
Continuity mistake: At the party right before Del Blaine and Jimmy Tong find their way down to the lab, Del is wearing dress sandals. When they get to the bottom of the stairs, she's wearing wedges. Her shoes change several times throughout the rest of the evening, including a third pair of chunky heels.
Continuity mistake: In the fight scene on top of the oil building, just after Jennifer Love Hewitt roundabouts the guy, she grabs Jackie Chan's hands, her hands are on either side of a pole. In the next shot, zoomed, their hands are on one side of the pole.
Continuity mistake: Jennifer's hair when Chan is fighting and holding a glass against her face changes from light brown in the close shots to dark brown-black in the wide ones.
Continuity mistake: In the funky singing scene the flower that Jackie's wearing is pink. Afterwards, at the kitchen, it is red.
Continuity mistake: When Devlin gets attacked, the big flow of blood on his head and face is totally different in the brief side shot we get and back to bleedy in the next front angles.
Continuity mistake: When Chan hangs the mink coat on the coat hanger its position differs between shots.
Continuity mistake: When Jimmy is driving the woman to work, he does a hand brake turn into an alley way and hits the wall with an audible crash, yet when he drives out of the alley there is no damage to the side of the car.
Continuity mistake: When the man drinks the poisoned water his face gradually dehydrates, becoming wrinkled and grey. However, when he kneels on the floor his skin colour is perfect and the wrinkles are gone.
Continuity mistake: The water that Chan spills on the picture of the bug appears and disappears all the time.
Continuity mistake: In the scene on top of the building when they are planting the bug, the guy grabs Blaine with his left arm around her neck. However, when she bits him, she bites his right shoulder.
Continuity mistake: When Chan and Jennifer are watching the map with the dams, they are standing a couple meters apart, but very close together a frame afterwards.
Continuity mistake: In the last scene, a man with a grey coat with blue and red stripes on the sleeve walks from left to right behind Jennifer. Shot on Chan, then cuts to Jennifer just 2 seconds later and the man walks by again, also from left to right.
Continuity mistake: When the bad guy flies up to open the hatch he swings his arm and lifts it up. In the close angle that follows the arm is down and he repeats the movement.
Continuity mistake: Jimmy kicks a door and makes a hole on it. Its shape differs between shots.
Continuity mistake: When Chan jumps in the car with his head totally covered in white powder, the exterior shots show his hair clean, the ones inside show it white.
Continuity mistake: When Chan's friend is talking with the biker, his hot dog falls. Seconds later it magically reappears in his hand for him to throw it at the biker.
Chosen answer: Since Del knew that the tuxedo actually belonged to Clark, she most likely thought that the watch and shoes did too.