I presume you mean where Season 4 ended, unless you have an inside line that I would love to hear about! heh.
The show regularly deviates from the comics in both small and large ways. The cliffhanger that our heroes left Season 4 in was not pulled directly from the comics, so there isn't an issue # that I could point you to. Others will have a better idea, but I would put the show somewhere in the early #60s, but again there isn't a direct correlation between the show and the comics.
As a fan of both the show and the comics I recommend you start with issue #1 and read straight through. There are significant differences between the two mediums in terms of story, and experiencing it as an illustrated and lettered page versus on the TV has its own benefits as well.
Good luck!