This movie got terrible reviews. Indeed, it got at least one non-review review that turned into a discussion of why some movies should never get sequels, but Hollywood obliviously makes sequels anyway, and ... etc., the writer was off the the races then, writing about everything except this movie.
But the theater was packed when I was there, and I enjoyed the show. Most people around me (admittedly not all) seemed caught up in it. This must have included at least some who weren't familiar with the original.
I'll avoid any spoilers, which seriously limits how much I can say about a movie of this sort. But I'll plow on anyway. There is a Big Reveal moment that takes place on a barge in the middle of the Thames. So if you find London scenery inherently fascinating, that'll be a plus for you.
The ending, the very ending, didn't work for me though. Perhaps the five minutes or so after the Big Reveal on the aforementioned barge might charitably be see as wind-down time. A lot of quasi-philosophical talking and some further reveals that are anti-climactic after the big one.
Loose ends still exist that could be tied up in a Part Three if everyone is willing.
The former Harry Potter, Daniel Radcliffe, plays a great Bad Guy. That's not a spoiler, BTW. His character is a bad guy from the moment he is introduced. Heck, the movie poster makes it plenty obvious. See above.
Anyway,, go and enjoy.