Continuity mistake: After prying off the lock to the storeroom with the pry bar, Doug drops it on the ground, but the next shot of him entering the storeroom shows it still in his hand.
Revealing mistake: Doug throws a grenade at Nakamura that lands just a few inches from a pile of leaves. The leaves explode rather than the grenade, they're a cover for the pyrotechnics.
Revealing mistake: On the beach, Doug and Tony rest against a heavy boulder that wobbles when they touch it.
Visible crew/equipment: The shadow of a large light or camera equipment is visible on the beach sand as Nakamura takes cover behind a boulder.
Continuity mistake: A bush on the beach that was used to mask the pyrotechnics of the grenade thrown at Nakamura disappears when Nakamura starts walking towards Doug.
Continuity mistake: When Dr. Nakamura exchanges greetings with the Time Tunnel team, they are far apart, but the next shot shows all of them much closer together.
Continuity mistake: When Tony lobs the grenade at Lt. Nakamura, it lands at least a foot away from his right foot, but the next shot shows the grenade about three inches away.
Continuity mistake: Lt. Nakamura is shown kicking the grenade Tony threw at his feet, but the grenade disappears before he kicks it, Nakamura is instead kicking a mound of sand.
Continuity mistake: After Lt. Nakamura disarms Doug, Nakamura is pointing his pistol to the left at Tony, then the next shot shows Nakamura pointing the pistol at Doug.
Continuity mistake: Sgt. Isugi turns his head slightly right and down to acknowledge Tony's injury, but the next shot of Isugi shows his head straight forward, addressing Doug.
Continuity mistake: When Doug takes cover in the cave, Nakamura fires two shots at him without chambering a new round in his bolt action rifle.