I 've read all "watches" - "Night watch","day watch", "twilight watch" and "last watch". Each book consists of three parts - three cases of Night Watch patrol. Both movies are based on a first two parts of a first book - "night watch"? but with few turns of second book as well. For instance, Alisa is one of the main caracters of Day Watch book - in first one her role is very secondary.
I like Lukianenko very much, he is really uses a heritage of soviet'russian sci-fi very good.