Under Act 2 of the game, when you get to Lyran's Hold and find your way into his Private Study, Lyran will appear (as a Lich) and will follow and attack you. Normally, you'd want to avoid him and get down to the cellar ASAP. However, you don't need to!
Just run out of his study with him following, then Recall back to Baldur's Gate. When you Recall back again, he ain't there anymore! Now, you can toddle down to the cellar at your own pace.
This was discovered on the European (PAL) version.