In the opening scene when Bruce Lee from enter the dragon is shown. Bruce Lee really says, "You have offended my family." The quote for this film is, "So you got in here, finally." If you watch Bruce's lips carefully he doesn't pause even for a second like the quote from this film does.
When Billy ascends to the top level of the restaurant to confront Dr. Land, only to find that he has apparently slit his wrists, the boxing bag and staircase from the fight with Hakim can be seen in the spliced-in footage of Bruce Lee.
At the beginning of the movie when Billy, Anne and Jim Marshall were talking, Marshall told Billy that Charlie Wang was fished out of the harbour the next day but right when Billy goes to fight Hakim, behind him you see Charlie's dead body lying there.
The footprint on Billy Lo's chest changes in darkness several times (considering ONLY the Bruce Lee scenes), especially during the fight with Hakim. Also at one point, the footprint is backwards for two or three quick clips. Also, when Hakim kicks Billy Lo, his toes actually do not touch Billy Lo to leave the print. Martial artists are taught to kick toes up. If slowed down,the connection can be seen where the toes never touch Billy Lo's chest.
During the first fight scene, we see a guy in a green jump suit is running at Billy and is back kicked. However when the kick forces the guy in green to flip, it is a guy in a black jump suit that flips yet he wasn't the one that was kicked. Then the guy in the green jump suit is kicked again when it should of been the guy in the black jump suit to receive that blow because the guy in green should of flipped after being kicked.
When Billy is proceeding to Hakim's level, on the bottom of the staircase, you see Chiech Yuan's body appear out of the blue. Same with when he was fighting the gold belt judo master. At the beginning of when they were fighting, there was no at the bottom but then when Billy is proceeding to the next level, it appears
When Billy is thrown over the guy's shoulder, we see the same set of nunchakus from Pasqual's level. Billy threw his nunchakus down on Pasqual but on the second floor when he is fighting the judo guy, they're there again.
The condition and style of Billy's running shoes changes during the final fight scenes. In some scenes they are brand new and in other scenes, they are old sneakers taped to resemble the shoes that Bruce Lee wore. A good example of this is when Billy approaches his nunchuck bag before his fight with Pasqual. You can clearly see that the his shoes are old and the black stripe pattern is actually made by strips of black electrical tape.
Just before his fight with Billy, Pasqual picks up two Filipino escrima sticks and you can clearly see that one stick is only half the length of the other stick. Moments later, the sticks Pasqual uses are equal length.
Throughout the fight in the dressing room of the theater people get punched in the face yet not a single person bleeds. However during the fights at the mansion, the climax, and Carl Miller they bruise and bleed. In reality if somebody gets punched at least twice chances are they'd bleed from their nose and mouths.