[MikeA]

Does anyone know why Standard's Adventures Into Darkness started at #5, i presume it continued from another title but I can't find any info.

[MarkWarner]

I looked at GCD and no mention so I thought I'd see if I could spot the first 5 issues by looking at the Standard Titles we have  https://comicbookplus.com/?cid=810

And there lies the answer my dear Watson!

The were no  #1-5 ... the same as for:
Best Romance
Boots and Her Buddies
Crime Files
Date With Danger
etc etc etc

They started lots of titles at #5!

[SuperScrounge]

Actually a number of Standard titles started at #5.

Adventures into Darkness
Battlefront
Best Romance
Boots and Her Buddies
Brick Bradford
Broncho Bill
Crime Files
Date with Danger
Dear Beatrice Fairfax
Exciting War
Freckles and His Friends
Gang World
Intimate Love
Jet Fighters
Jetta of the 21st Century
Joe Yank
Johnny Hazard
Little Angel
Lost Worlds
Lucky Duck
Mel Allen Sports Comics (#5 only on cover)
My Real Love
New Romances
Out of the Shadows
Peter Pig
Popular Romance
Reg'lar Fellers
Ricky
Roger Dodger
Sniffy the Pup
Television Comics
This Is War
Thrilling Romances
Today's Romance
Tuffy
The Unseen
Who Is Next?

Guess some editor was superstitious. Dates of the books starting with 5 run from 1947-1953.

[MikeA]

Wow that is so bizarre.

[kusunoki]

I seem to remember hearing somewhere that Standard started their books at #5 because they thought that people would be more likely to buy books that appeared to have established themselves and survived beyond the first few issues.

[SuperScrounge]

I've heard that (after my previous post obviously).

I've also heard that apparently publishers had to pay some kind of postal fee for a first issue so some publishers would just skip #1 issues as a way to trick the post office (mostly fly by night operations that didn't put out a lot of comics so might not apply here).

[atomickommiecomics]

I've heard that (after my previous post obviously).

I've also heard that apparently publishers had to pay some kind of postal fee for a first issue so some publishers would just skip #1 issues as a way to trick the post office (mostly fly by night operations that didn't put out a lot of comics so might not apply here).

I believe you're thinking of the "second class postage license" each publication was granted to ship magazines.
Since the publisher had to pay for one for each title, they would try to keep titles similar, even as the magazine changed genres, to avoid paying for a new license.
The classic example of this was EC Comics' Moon Girl, which became Moon Girl Fights Crime with #7 as it switched genres from superheroine to gritty crime.
Then, only two issues later, the book became A Moon, A Girl...Romance! as it became a love comic with #9!
But as of #13, the comic became the sci-fi title Weird Fantasy, and EC had to finally cough up a new second class license fee!