On the topic of Selene after she bites Alexander I don't think she is a hybrid. He said she was the new race of vampire. She's stronger and can be out in the light.

On the topic of william and marcus, if you paid attention in the movie you would have learned that it wasn't a fact that they all would die. Someone made the speculation that all vampires and lycans would die if that happened and Viktor was too chicken to test that theory.

As for Alexander being immortal, I have no idea how. I do expect that when they make the third movie they MIGHT explain it.

I certainly hope there's a third movie...the epiloge just screamed 'sequal!'.

Uhh.. it's already been said there will be. I watched a show about it. The story was designed to be a trilogy.

Finally got to see Underworld 2. Not as good as the first IMO. This one didn't have the scheming that tickled my fancy.