Professor Starr asked me to come and see his latest discovery! It's probably terrific, since he's the greatest genius alive today in the year 2055! 
Action Comics #205 is an issue of the series Action Comics (Volume 1) with a cover date of June, 1955.
Synopsis for Superman: "Sergeant Superman"
Given the rank of sergeant so that he can participate in Army war games, Superman must solve the mystery of why a private who contantly botches things must remain in the games.
Appearing in Superman: "Sergeant Superman"
Featured Characters:
Supporting Characters:
Antagonists:
Other Characters:
- Fred Carson (Single appearance)
- Jim Carson (Single appearance)
Locations:
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Synopsis for Tommy Tomorrow: "The Super Planeteers"
Colonel Tommy Tomorrow, Planeteer of 2055, is transferred thru time into the 22nd Century, by a future criminal scientist's Time Ray. This is an accident, what the scientist, Dr. Ultra, really wants is the written formula that Tommy happened to be holding at the time of the transfer. Tomorrow's antique 21st century weapons are useless against Dr. Ultra's 22nd-Century technology, and he is disdainfully kicked out of the villain's lair to rove freely across the unfamiliar world. He can't get back to his own time anyway, because the gangsters used up their last charge of the rare Timeum metal to work the Time Ray just that one time.
Col. Tomorrow makes his way to a Super Planeteers station, and tells his story. All of their technology is amazing to Tommy. Dr. Ultra meanwhile has created invulnerable protective suits from the indestructible 21st-Century plastic, and he and his henchmen wear these while robbing an interplanetary jewelry store. The Super Planeteers are unable to prevent their escape with a lot of loot.
Tommy Tomorrow devises a plan, involving a phony time capsule and some artifacts from a "Museum of the 20th Century." He elaborately dupes the crooks into smoking some specially-treated cigars, and looking at some specially-printed paper pages, which partially paralyzes them. Tomorrow then peels them out of their protective suits and arrests them.
The Super-Planeteers have a small supply of Timeum, which they use to send Tommy back to the year 2055.
Appearing in Tommy Tomorrow: "The Super Planeteers"
Featured Characters:
Supporting Characters:
- Professor Starr, 21st-century scientist (Single appearance)
- Super-Planeteers of 2155
Antagonists:
- Doctor Ultra, 22nd-century scientist (Single appearance)
- two assistants
Locations:
Items:
- Starr's 21st-century indestructible Super-Plastic (Formula is destroyed)
- Ultra's 22nd-century Time Ray
- Ultra's 22nd-century Time Television
- Timeium
Vehicles:
- Super-Planeteer (2155) 4th-dimension-spanning spaceship,
Synopsis for Congo Bill: "The Mystery of the African Polar Bears!"
Appearing in Congo Bill: "The Mystery of the African Polar Bears!"
Featured Characters:
Supporting Characters:
Antagonists:
- Jim Jackson (diamond smuggler)
Other Characters:
- Alec Blake (diamond smuggler)
Locations:
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Notes
- Tommy Tomorrow: "The Super Planeteers" is reprinted on the book Mysteries in Space: The Best of DC Science-Fiction Comics
- "Timeum" is a rare metal that will exist, in small, precious quantities, in the 22nd Century.