Investigating Shipwreck Island

The Whirly Knife

The Whirly Knife crashes and explodes

Killian, captured in Zoltar's place



Secret Island

Written by: Jack Paritz
Alternate Title: Man-O-War Typhoon
Production Number: 59
Airing Number: 37
Script Completion Date: 8/24/78
Episode Completion Date: 10/31/78
Preview / Trailer: Preview
Credit Version: A
Title Card Version: B
Official episode synopsis

..To test out new weapons to consider them for future use..

..To discover the source of recent weather anomalies near the Bermuda Triangle.

Stay tuned! Coming up next on Battle of the Planets!
G-Force combats a hostile alien spaceship over the mysterious Bermuda Triangle! Could this strange and deadly UFO be responsible for the scores of ships and planes that have been reported missing at sea? Is G-Force about to be pulled down into the treacherous Bermuda Triangle and vanish without even a trace?
Be sure to watch this exciting episode, coming up next!

7-Zark-7 is informed of intermittent typhoon activity in Sector 11. In the area, the ocean starts churning around a fishing vessel, and two massive monster machines burst from below the sea and streak skyward. Meanwhile, G-Force is relaxing in their ready room discussing a ship that has gone missing in the Bermuda Triangle, when 7-Zark-7 calls in to send Mark and Princess to investigate its disappearance.

The mysterious activity is taking place near Shipwreck Island and Mark and Princess then take a speedboat out to check it out. Princess is uncomfortable on the island because it looks threatening and the two spend the whole day waiting for any kind of sign. When night falls, they’re rewarded with the appearance of two giant machines that rise from the ocean. They then suspect there is a Spectra base on the island. As they watch the two machines, a water spout appears and destroys them both with ease. Mark thinks they have just witnessed a Spectra weapons test.

As they discuss what they saw, they spot three lobster tanks heading their way. When one stops nearby they decide to try to get inside it. They overpower the driver, Mark takes his uniform and they follow the line of tanks back into the base. Once inside, Mark leaves Princess in the tank and investigates on his own.

The tank squadron commander and disguised Mark are greeted inside by Dr. Killian. He orders the pair to follow him to meet with Dr. Wold. They are taken inside a massive construction facility where a number of Spectra monster machines are in various stages of completion. They continue on to a small room where Dr. Wold is waiting for them, along with a friend - Zoltar! Killian explains that they are gathered to witness a demonstration of their newest weapon. Zoltar informs Dr. Wold that if successful, Spectra will reward him with the highest position of authority; the command of their entire scientific community.

Meanwhile back at Center Neptune, 7-Zark-7 gets a call from Princess informing him that they have discovered a new Spectran base at Shipwreck Island. She also tells 7-Zark-7 that Mark has infiltrated the Spectran ranks and 7-Zark-7 then sends the rest of G-Force to join Mark and Princess at the island.

Killian shows Zoltar a tape of what their new weapon, the Whirly Knife, is capable. Zoltar is impressed but wants to see a live demonstration. Mark sneaks back to the tank to tell Princess he’s going along with Zoltar, Wold and Killian on the test. After Mark leaves, Princess wonders why she is allowing him to tackle the mission alone. Without telling him, she decides to follow along.

As the Whirly Knife demonstrates its power, Zoltar agrees to order a fleet of them from Dr. Wold. A soldier interrupts their revelry with the news that G-Force is on its way. Killian tells Zoltar the Whirly Knife will easily take care of them.

On board the Whirly Knife, Mark attempts to sabotage it. He is stopped however, when Killian sticks a gun in his back. Killian is about to unmask Mark, when he himself is stopped by another Spectran soldier. After Killian slinks away, the second Spectra soldier reveals himself to be Princess.

The Phoenix dodges the attacks of the Whirly Knife and Dr. Wold decides to utilize the water spout to defeat G-Force. As the water spout pulls the Phoenix in, Mark and Princess fight hand-to-hand with a legion of Spectran soldiers. Making short work of the soldiers, Princess sets about sabotaging the Whirly Knife. The explosion she initiates succeeds in freeing the Phoenix and disabling the new Spectra machine. As the ship falls, Killian gives the order to abandon it. Mark and Princess get to the control room and find Wold and Zoltar. Mark grabs Zoltar and attempts to unmask him him right there. An escape craft rockets away from the dying Whirly Knife and Mark and Princess, with Zoltar in tow, decide to escape to the Phoenix while they can.

The Whirly Knife crashes into Shipwreck Island and explodes. Back on board the Phoenix, Mark finally makes good on his threat to unmask Zoltar, only to find.... Killian. The real Zoltar forced Killian to take his place while he got away in the escape craft.



Name: Whirly Knife
Type: Mechanical Aerodyne
Body Shape: N/A
Origin: Planet Spectra
Sighting: Planet Earth

Weapons: Rotary Knives, Giant Bore, Waterspout .........Generator
Flight Capable: Yes
Crew: Yes
Status: Destroyed

The Whirly Knife machine held an impressive amount of weapons, the most destructive of which was its Waterspout Generator. While spinning at a high rate of speed, it could pull up a gigantic waterspout capable of destroying other giant Spectra monster machines. Its Giant Bore could drill into the hulls of opposing craft and its Rotary Knives could cut through mountain tops.The Whirly Knife was defeated when Princess set an explosive charge to knock out its power center. It was equipped with an escape craft that Zoltar used to get away.

Not only does 7-Zark-7 monitor space for signs of trouble, he is also tasked with watching for severe weather manifestations on Earth such as earthquakes, floods and tornadoes

Spectra manufactures at least some of their massive monster machines right on Earth



Unless otherwise stated, all program material, situations, descriptions and depictions are copyright © Tatsunoko Production Co., Ltd.