I can't vouch for 2 or 3 because I never played it.
Another great thing about the series - each one improved on its predecessor. BT 3 > 2 > 1. Each is deeper than the last. Not to mention darker.
All I'll say about BT 3 Thief of Fate: your Chronomancer mage allows you to travel in time - including to locales like Berlin 1945 on the eve of Hitler's defeat. It's. Awesome.