In the opening sequence of Fast & Furious, set in the Dominican Republic, Dom and Letty and friends are stealing tanker trailers from a 4-tanker truck. The first tow truck steals one tanker of gas (leaving 3 by my math). The next tow truck shows steals two tankers (which should leave one left, correct?). The following scene shows the victim truck with two tankers left. These two tankers are needed in order to trap Dom and Letty in their Buick Grand National between the tractor/trailer at the edge of the cliff, and the rolling fireball tanker threatening to crush and burn them.

This slip-up should have been caught and could have been easily edited out by deleting about 2 seconds of unnecessary film.