Is this comic series based on the OTR Shadow character?
Its a little more complicated than that. Originally, the character was invented to be sort of an announcer to introduce radio dramas based on mystery pulp magazine stories from publisher Street & Smith. Eventually, he got to be so popular, that people started asking for magazines featuring the character. So, Street & Smith introduced The Shadow Magazine as a bi-monthly, then within the first three months it sold so well it went monthly, and then bi-weekly. From that point the character moved from an announcer to the star of the radio show. As the pulps were starting to decline and comics took over, Street & Smith introduced a line of comics that featured the Shadow and (which looks to me anyway) was a blend of the radio and pulp iterations (there are some significant differences between the two).
In the 70's and 80's the comic character was resurrected, I think it part, because the pulp stories were reissued as paperback novels, and the character has been a recurring hero ever since. I'm sort of partial to the Michael Wm. Kaluta and Denny O'Neill versions, but I did enjoy the two-part story from The Shadow Strikes series I picked up. I seem to recall reading one issue from this series several years ago, but have no idea where I got it or where it went.
The neat thing is that each iteration (radio, pulp magazine and comic) are very different (and that doesn't even begin to include the film and TV versions). I know a lot of purists say that the pulp version is the "true" version, and I lean in that direction somewhat, but I do enjoy the others as well (except for the comic versions that place the character in the modern day).
If you're interested, there's a new podcast that just went live about a month or two ago called 'The Shadow Fan Podcast' (available via iTunes). He covers all the versions quite nicely.