Real Name: Dr. Herman Frayne

Identity/Class: Human mutate

Occupation: Would-be world conqueror (savior in his own mind); former student and teacher of ecology

Group Membership: None

Affiliations: Caeceleon, Maelstrom, Phaeder; Gremlin and Lazard (agents);
the Hydro-Men/Hydro-Base Amphibians (Dr. Henry Croft, Betty Dean Prentiss)-creations

Enemies: Atlanteans, Namorita, Tamara Rahn, Scarlet Witch (Wanda Maximoff), Sub-Mariner (Namor McKenzie)

Known Relatives: None

Aliases: None

Base of Operations: Hydro-Base, floating in the North Atlantic Ocean, outside U.S. Territorial waters

First Appearance: Sub-Mariner I#61 (May, 1973)

Powers/Abilities:  A gifted scientist, Dr. Hydro was amphibious, able to breathe on land or underwater--he did not possess gills, but rather he was able to extract dissolved oxygen from water via specially adapted pores in his scaly green skin.

Additionally, he later displayed the power to transform himself into a greenish cloud of water-vapor, which made him invulnerable to physical harm--this was an ability that apparently he alone possessed, as none of his other Hydro-Men demonstrated such a trait.

Dr. Hydro and his men used a variety of weapons utilizing "Hydrocules." He also had lots of other Kirbytechâ„¢ weapons, such as hypnotic discs that could render people unconscious, and a giant "atom" prison.

He had access to a mutagenic compound with which he could mutate others into amphibious humanoids.

Hydro-Base was equipped as a military fortress and had many advanced weapons, including electrical force fields (see comments).

His soldiers were armed with conventional weaponry (as well as some more a that danged Hydrocule technology).


Height: Unrevealed (6'; by approximation)
Weight: Unrevealed (180 lbs.; by approximation)
Eyes: Green
Hair: Brown

(Sub-Mariner I#61 (fb) - BTS) - Dr. Herman Frayne was once a normal man, and a student and teacher of ecology. Somehow, he got the idea that the only way for mankind to survive was to return to the sea.

(Marvel Two-in-One I#72 (fb) - BTS) - Frayne was supplied by Maelstrom and Phaeder with a compound derived from the Terrigen Mist (the compound responsible for the mutation of the Inhumans).

(Sub-Mariner I#61 (fb) - BTS) - Frayne used the Terrigen compound to mutate himself into an amphibian--he presumably gained his additional powers via similar means. Dubbing himself "Dr. Hydro," he began the construction of Hydro-Base, and hired a number of agents that he similarly mutated to assist and serve him. He initially dreamed of building a city beneath the waves, but he later decided it would be easier to take Atlantis for himself.

   Dr. Hydro had his men hijack airplanes that were headed to Florida, and they forced them to land on Hydro-Base--four flights had been captured. Once the planes landed at Hydro-Base, the passengers were taken into a chamber, where Hydro exposed them to the Terrigen derivative, mutating them into amphibians as well. Many of these people, seeing the futility in returning to the surface world, apparently joined Hydro's mission.

(Sub-Mariner I#61) - Namor's allies--Namorita and Betty Dean Prentiss--were passengers aboard what became the fifth hijacked flight. When they arrived at Hydro-Base, all the passengers were herded into a chamber--Namorita, unsure of what to expect, and not wanting to reveal her presence too soon, played along. Then Dr. Hydro exposed the captives to a chemical mist and informed them that they would be transformed into amphibians in the process.

   Meanwhile, Namor learned that his friends' plane had been hijacked; since he lacked any means to locate them, he went to the airport and stowed away on the next Florida-bound flight--he grabbed hold of the plane's rudder and rode on the outside.

   "Fortunately," the plane was eventually hijacked, and upon arriving on Hydro-Base, Namor was attacked by Dr. Hydro and his agents. However, Namor was weakened, for the winds rushing over his body during the flight had left him dehydrated; as he desperately tried to reach the water to replenish his strength, Namor was rendered unconscious and captured when he made contact with an invisible electrical force field.

   When Namor revived, he found himself imprisoned within what appeared to be a "mammoth atom". The gloating Dr. Hydro then activated his giant monitor screen and showed Namor how his armada was about to begin an assault on Atlantis.

(Sub-Mariner I#62/1) - Namorita (who had been unaffected by Hydro's transformation process) broke away from her fellow mutated passengers and made her way to the main control room, where she found the imprisoned Sub-Mariner; she sabotaged the control panel and freed Namor from the "atom" prison.

   Meanwhile, Tamara rallied the Atlanteans to fight back against Hydro's soldiers, then Namor and Namorita arrived and joined the battle, and Hydro's forces were swiftly routed. Dr. Hydro himself challenged Namor to face him in combat, but the villain was accidentally struck from behind by one of his own submarines that was out of control. Believing that Hydro was mortally wounded, Namor tried to convince him to reveal how the mutated amphibians could be made human again; but with his "dying" words, Hydro told him there was no cure--Hydro was believed to have died at that point.

(Sub-Mariner I#63/1 (fb) - BTS) - But agents of Dr. Hydro recovered his "corpse," and he was revived. Hydro began a new plot to take Atlantis by generating intense heat from a nearby volcanic crater on the ocean floor.

(Sub-Mariner I#63/1) - As the Atlanteans began to feel the heat (in more ways than one), Namor investigated the volcanic crater; but he was caught in a Hydrocule net and dragged into a sub-sea cavern, where his startled eyes beheld the very-much-alive Dr. Hydro! After he was released from the net, Namor swam to attack Hydro, but just as his powerful fist connected, the villain turned to mist and escaped. As Hydro's disembodied mocking laughter filled the cavern, Namor vented his rage against some of the villain's soldiers.

   Namor returned to Atlantis and took command of a squadron of Atlantean water/steam-propelled warships, and the fleet neutralized the volcanic crater. Namor then took his own craft to confront Hydro again; but his time, when Hydro turned to mist, Namor used his craft's  jet intake system to draw Hydro's gaseous form inside, and trapped him within a containment tank.

   Later, Namor went back to Atlantis and had the containment tank placed into a fusion chamber, to have the unbreakable container hermetically sealed. Afterward, the "indestructible" tank was placed in a torpedo tube and launched back to the surface (see comments).


(Scarlet Witch III#1 (fb) - BTS) - As part of the Slow Science Movement Hydro created the first of his great Hydro-Fauna called Caeceleon. Doctor Hydro led a cruise ship in the Pacific Ocean to show off Caeceleon to a bunch of rich, bored folks that followed Hydro's science. Upon arrival Hydro jumped off the ship and wrangled Caeceleon, his creation, which hungered for meat after a long gestation.

(Scarlet Witch III#1) - Doctor Hydro rode the gigantic monster, which ripped apart the cruise ship to feast on Hydro's followers. The Scarlet Witch arrived, teleported Caeceleon to Monster Isle, fixed the cruise ship and punished Doctor Hydro by trapping him in a pocket reality that resembled the New Jersey DMV.

Comments: Created by Steve Gerber, Bill Everett, and Winslow Mortimer.

Namor intended for Dr. Hydro to remain trapped in the containment tank until the end of time, and thought it was quite likely that he would starve to death within it. That is a pretty flimsy definitive end to a character. There's no reason to assume his gas form would need food or energy. The tank could have shattered on impact, or it could have been found and opened by anyone with the means to do so. The only reason that Hydro hasn't returned is that he's such a lemon of a character.

The Hydro-Men (500 of them) were eventually returned to human form by the Anti-Terrigen Compound in Marvel Two-In-One I#71.

Hydro-Base has an entry in the Official Handbook of the Marvel Universe Deluxe Edition#6 and it is indeed the same base later used by Stingray and the Avengers, until it was sunk during the Acts of Vengeance.

It's unclear (and moot as moot can be!) if Hydro was independently wealthy, or if not, from where he gained all of the funding to build Hydro-Base, pay his agents, etc. Perhaps that, too, came from Phaeder and Maelstrom.
--Dr. Hydro's connection to Maelstrom was revealed in Marvel Two-in-One I#72, and also mentioned in Official Handbook of the Marvel Universe Deluxe Edition#7: Maelstrom.

According to, Bill Everett took ill after finishing only the first four pages of Sub-Mariner I#61, and he passed away a month after that issue was published, which is why he never actually drew Dr. Hydro in the story itself.
However, Everett did draw Dr. Hydro on the cover of #61, but he looked nothing like he appeared in the story (...I think the character on the cover looked more like the Mad Thinker).

Dr. Hydro and his Hydro-Men may have been created as an homage to Bill Everett's 1940s hero Hydroman, who--similarly to Dr. Hydro--could transform himself  into water.--Ron Fredricks

Profile by Snood. Expansion by Ron Fredricks. Update by Markus Raymond (Scarlet Witch).

Dr. Hydro and the Hydro-Men (aka the Hydro-Base Amphibians, the mutations of Dr. Hydro) have no known connection to:

Gremlin has no known connection to:

Lazard has no known connection to:

Hydrocule weapons

Invented by Dr. Hydro, Hydrocules were some type of enlarged water molecules... or condensed water... or something (...Dr. Hydro never gave a clear explanation); they were used in two variations for weaponry.

When Hydro first confronted the Sub-Mariner, he used a high pressure gun which fired baseball-sized projectiles composed of Hydrocules.

Later, Dr. Hydro's soldiers ensnared the Sub-Mariner in unbreakable nets made of specially-treated Hydrocules.

--Sub-Mariner I#61 (gun); Sub-Mariner I#63/1 (nets)

"atom" prison

One of Dr. Hydro's devices, it was located in the main control room of Hydro-Base. The ceiling-mounted device projected a spherical force field that was used to detain the Sub-Mariner--Namor himself compared it to a "mammoth atom".

Namor found the prison to be unbreakable, because the harder he pressed against it, the stronger it became, and the weaker he grew.

But Namor was eventually freed when his cousin Namorita sabotaged the control panel.

--Sub-Mariner I#61 (Sub-Mariner I#61, 62/1


He was one of Dr. Hydro's agents, as well as one of the amphibious Hydro-Men.

It was he who hijacked the jet carrying Namorita and Betty Dean Prentiss. Dr. Hydro had supplied him with an hypnotic disc that rendered the plane's passengers and crew unconscious, then Gremlin flew the plane to Hydro-Base.

(Comment: "Gremlin" probably wasn't his real name, but just a nickname based on the supposed stories of the mischievous creatures that sabotaged aircraft during World War II.)

--Sub-Mariner I#61 (possibly BTS in 62/1+63/1)


Lazard (first name unrevealed) was another of Dr. Hydro's amphibious agents.

He hijacked the jet on which Namor was stowing away. He had a similar hypnotic disc as Gremlin.

(Comment: Judging by his dialogue in the first image, Lazard may have had a bit of a rivalry going on with Gremlin.)

--Sub-Mariner I#61 (possibly BTS in 62/1+63/1)

Dr. Hydro's casket

During his final undersea encounter with Dr. Hydro, the Sub-Mariner confronted the villain with a specially-modified Atlantean warship.  When Hydro transformed himself into a greenish cloud of water vapor, Namor activated his craft's water-intake pump and drew in the villain's gaseous form, trapping him within a containment tank.

Namor then returned to Atlantis and had two of his men remove the tank and place it inside a fusion chamber, to hermetically seal the container and keep the semi-solid Hydro a prisoner for the rest of his life.

Afterward, Dr. Hydro's casket was put into a torpedo tube and fired back to the surface--exactly where it may have landed, and its eventual fate, are both unrevealed.
--Sub-Mariner I#63/1

images: (without ads)
Sub-Mariner I#61, p7, pan5 (Main Image - at Hydro-Base, Dr. Hydro (center) commands his soldiers to removed prisoners from hijacked jet)
Sub-Mariner I#61, p7, pan2 (Headshot - Dr. Hydro)
Sub-Mariner I#61, p9, pan1 (Dr. Hydro introduces himself to prisoners)
Sub-Mariner I#63/1, p12, pan2 (Dr. Hydro transforming into water-vapor)
Sub-Mariner I#61, cover ("Dr. Hydro")
Sub-Mariner I#61, p16, pan3 (Dr. Hydro fires Hydrocule gun at Sub-Mariner)
Sub-Mariner I#63/1, p7, pan1 (Dr. Hydro's soldiers use Hydrocule nets to ensnare Sub-Mariner)
Sub-Mariner I#61, p20, pan1 (Sub-Mariner trapped inside "atom" prison; Dr. Hydro (foreground))
Sub-Mariner I#62, p2, pan1 (Sub-Mariner trapped inside "atom" prison)
Sub-Mariner I#61, p5, pan5 (Gremlin uses hypnotic disc on plane passengers)
Sub-Mariner I#61, p7, pan4 (Gremlin unmasked, reporting to Dr. Hydro)
Sub-Mariner I#61, p14, pan1 (Lazard enters cockpit with hypnotic disc)
Sub-Mariner I#61, p14, pan2 (Lazard takes control of plane)
Sub-Mariner I#63/1, p12, pan3 (Dr. Hydro transformed into water-vapor, being drawn into Sub-Mariner's warship)
Sub-Mariner I#63/1, p13, pan1 (Namor commands two Atlanteans to carry containment tank with Dr. Hydro to fusion chamber)
Sub-Mariner I#63/1, p14, pan2 (Dr. Hydro's casket launched from torpedo tube)
Sub-Mariner I#63/1, p14, pan3 (Dr. Hydro's casket plummets downward)
Scarlet Witch III#1, p2-3, top panel (riding Caeceleon)

Sub-Mariner I#61 (May, 1973) - Bill Everett/Steve Gerber (writers), Bill Everett/Win Mortimer (pencils), Bill Everett/Jim Mooney (inks), Stan Goldberg (colors), Charlotte Jetter (letters), Roy Thomas (editor)
Sub-Mariner I#62/1 (June, 1973) - Steve Gerber (writer),  Sam Kweskin/Frank Giacoia (pencils), Frank Giacoia (inks), Petra Goldberg (colors), Shelly Leferman (letters), Roy Thomas (editor)
Sub-Mariner I#63/1 (July, 1973) - Bill Everett/Steve Gerber (writers), Sam Kweskin/Syd Shores (pencils), Syd Shores (inks), Glynis Wein (colors), Artie Simek (letters), Roy Thomas (editor)
Scarlet Witch III#1 (March, 2023) - Steve Orlando (writer), Sara Pichellit (artist), Elisabetta D'Amico (inking assistant), Alanna Smith (editor)

First Posted: 05/16/2002
Last updated: 04/12/2024

Any Additions/Corrections? please let me know.

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