New this month Continuity mistake: The professor mentions he can't drink vodka with the Russians because he's allergic to alcohol, yet in the episode "Man With A Net" (with Lord Beesley), he drinks a strong alchoholic drink he made along with everyone else with no signs of any sickness, or reaction preventing him from drinking it.
New this month Plot hole: Mr. Howell suggests the switching vodka for water idea, and then Gilligan empties one vodka bottle and puts water in it for the castaways. But there's no way this plan could have gone through since no castaway knew in advance how much vodka or how many bottles the Russians had to execute such a plan.
Continuity mistake: In the episode with Phil Silvers as Harold Hecuba (a.k.a. H.H.), H.H. goes out to change costumes. When he comes in as Ophelia the stage door first closes behind him, then falls off the hinges. The shot cuts to the Castaways, then back to H.H., and the door is back on the hinges.
Plot hole: The scientist yells for Igor to capture the escaping Castaways, to which Igor responds "capture them yourself" in Ginger's voice. The scientist appears surprised to find out Igor is not Igor, but how can this be? He had to be the one to pull the lever to switch everyone's personalities and bodies around, so he should have already known.
Visible crew/equipment: Toward the end, the group is around the table, talking about Gilligan. Then they see a pear and a bunch of grapes float over to a plate at the head of the table. Skipper goes over and addresses the invisible Gilligan. If you look at the top of the hut, you can see the wires used to make the fruit float. Also, earlier in the hut with Ginger, when Gilligan bit the pear, you can see the wire holding the pear as it shakes after the bite.