At the end of the movie, when Doc comes back from the future (2015, to be exact), the DeLorean runs into a garbage can in front of Marty's house. When the DeLorean runs into the garbage can, if you look real closely, you can see that the driver is clearly not Doc (Christopher Lloyd), but a stunt driver. After this, when Doc gets out of the car, he's wearing futuristic sunglasses. Clearly, the stunt driver doing the stunt was not wearing the glasses that Doc is wearing when he gets out of the DeLorean. Geez, you'd think the filmmakers would do a better job of disguising the stunt doubles to look like the real actors.