Continuity mistake: When Mason pulls Goodspeed out of the water in the next scene they are both completely dry hair, clothes, face but when Goodspeed is picked up his hair, clothes and face are wet.
Continuity mistake: In the beginning of the movie as Hummel visits his wife's grave, the rain changes from shot to shot, in some it's raining heavily, while in others barely at all. In the shot just before we see who's grave it is you can see blue sky behind Hummel.
Visible crew/equipment: Right near the very end where you have the overhead shot of the bombs hitting the back of the island you see Stanley Goodspeed being thrown through the air by the force of the explosion, and into the water. As he is flying through the air you can see the wires he is attached to, to make him fly.tattoojunkie
Plot hole: When Mason and Goodspeed are locked in the cells together Goodspeed asks Mason what he did to pass the time when locked in the cells on Alcatraz. Mason mentions he dreamt of meeting his daughter one day. However it has previously been stated that Mason was in the rock 1962-63 but his daughter wasn't born until the 1970s.
Visible crew/equipment: In the interrogation room, it shows the mirror reflecting Mason, Goodspeed and the other guy. Look carefully: for a split second you can see a shine of a watch, then an arm, of the cameraman.
Continuity mistake: When Goodspeed is driving through the warehouse in his yellow convertible then smashes through the big glass window you'll notice that it's simply not possible. The window is about a foot off the ground, which means there would have to be a ramp. If you look closely there are two hinges at the bottom of the window which show where the ramp ends. The fact that there's a ramp at a dead-end window was poorly planted there by the crew.
Deliberate mistake: When one of the captains throws the grenade while Mason is in the bath, it coincidentally rolls to a left into the bathtub area, instead of rolling straight.