Book series about teens who work for a time travel agency and meet a Roman soldier

Question

I read this book series about 8 years ago now; it was kinda your usual young adult fare, as far as I can remember. I think there were two teens (maybe more?) that somehow became a part of this time travel agency and they had to go back in time to keep things on track.

The thing I remember most was them encountering a Roman soldier, who wasn't the backward denizen of the past they expected, but just a generally very smart and competent person who got the hang of modern tech very quickly. Sorry, it's not much to go on. Thanks.

Answer 1

This might be the Time Riders series by Alex Scarrow. In that, three teens were recruited by being snatched out of time just before they would have died. Their headquarters is some abandoned rooms under a bridge, and the headquarters deliberately time loops over two days (so that there is less chance of its existence being discovered). The fifth book in the series is "Gates of Rome" in which the team is stranded in ancient Rome, and an alternate timeline comes into existence where the Romans have access to future technology. The series was published between 2010 and 2013.