1. The edge of the sky

 

"Two on a Raft"

Right off in the first episode, keen-eyed viewers might catch a reveal when Gilligan and the Skipper are on a raft surrounded by sharks. In the shot when the Skipper throws the sail, the false backdrop of the sky behind the water tank is visible. There are creases on the fabric, and a gap can be seen between the bottom and the water. It can pass for land, perhaps?

2. An invisible submarine

 

"So Sorry, My Island Now"

When Gilligan gets in the tiny Japanese submarine to seek help, he leaves the top hatch open. That's the joke. However, as Bob Denver is filming the scene, one can clearly make out his legs and feet splashing about the prop, even though he's supposed to be inside a submersible.

3. A scuba tank

 

"So Sorry, My Island Now"

Yep, same episode again — and, no, this is not Nessie. After Gilligan finally closes the hatch, he circles around the lagoon. We see the periscope darting around cluelessly. At points, you can catch the scuba tank of the prop man moving around the periscope. The film is sped up, so it's hard to catch.

4. Bob Denver's wedding ring

 

"They're Off and Running"

When did Gilligan get hitched? Early in the episode, as the Skipper and his little buddy race turtles, a wedding ring can be spotted on Gilligan's hand. Denver must have forgotten to remove it before filming.

5. The skyline of the island

 

"The Friendly Physician"

At the end of the episode, as the gang returns home on a small boat, buildings can be seen over the trees surrounding the lagoon. They are either studio structures or bits of the surrounding Los Angeles skyline.

6. The bubble maker

 

"Pass the Vegetables, Please"

No, the actors did not drink soap. At the close of the episode, as the seven sit around and eat, bubbles start flying from their mouths. In the shot when Mary Ann discovers her bubbly tummy, behind her face, you can make out what appears to be the metal clamp holding the effects hose to spit out the bubbles, or part of the machine.

7. Blink and you'll miss it

 

"Man with a Net"

In the episode, a lepidopterist comes to the island in search of the "Pussycat Swallowtail" butterfly. As he takes his leave, he knocks out the seven castaways. (What a guy!) They are supposed to be unconscious, but Natalie Schafer slips and opens her eyes.

8. Fruit on a wire

 

"Personal Magnetism"

We hate to spoil the illusion, but magic is not real. In this episode, pears and grapes float across the dinner table thanks to an invisible Gilligan. You can make out the wires used to lift the prop fruit, reflecting light up near the roof of the hut. Similarly, in the earlier "It's Magic," you can spot the wires used to levitate the table at the end.

9. The mysterious eighth castaway

 

Opening credits

Now this is our favorite little goof, as it opens up narrative possibilities. As the Minnow leaves port in the opening credits, when the lyrics proclaim, "Five passengers set sail that day," eight people can be counted aboard the boat. Ginger and Mary Ann sit up front. Gilligan and the Skipper stand up top. The Howells and the Professor are aft. That leaves the mysterious man piloting the boat. What ever happened to him?

SEE MORE: 22 FASCINATING FACTS ABOUT 'GILLIGAN'S ISLAND'

 

There are more secrets in the opening credits. Plus: learn Gilligan's first name and the location of the island! READ MORE