If you watch this on a holiday weekend, it’s only because you’ve got pre-teens around. BBC America used all its Doctor Who golden-anniversary promotional muscle to promote this new series import, which premiered last week. It turned out, however, to be a decidedly juvenile affair, with a tone, and a script, that made it seem like a TV sibling of Young Hercules. Oh, and Hercules is in this new series, but not as a teenager – though there is a young Jason. And a young Pythagoras. But if there’s a triangle in play, it’s not a romantic one.