This was composed by Bear McCreary, who you probably know best for his work on Battlestar Galactica and a few other things. But to hear the urgency of the strings, you’d almost think it were a Bernard Hermann score:
It’s not as fun or goofy as the fanmade sequence was, but the show isn’t that fun or goofy either (this is not a criticism). Here’s McCreary discussing why he made the music the way he made it:
McCreary notes here that the show has so little non-diagetic music as is that when you hear the strings coming, you know to pay extra attention. This is a pretty common practice for horror or suspense films, but I haven’t seen it done much on television, which makes me excited for the score to this series.