There’s actually 3, depending on what you’re counting I guess. Betrayal, Return To, and the Antara game. Return To was a very different gameplay style. I got a copy of the CD only, but never played it. Antara was similar style to Betrayal, but with better graphics, sound, etc.
My brother and I both loved the original Betrayal. I never finished Antara, because back when I bought it my computer was too slow. I haven’t had a chance to play it again.