Wesley's fears for Angel and especially his baby son he's been harboring for a while after discovering the (we later learn) fake prophecy have finally overcome him. He plots behind Angel's back, and behind the backs of all his friends to take Connor away from his father, where he thinks the child will be safe and the prophecy, "the father will kill the son", won't come true. He asks Angel to take the baby to his apartment for a night, while what he really means to do is take him away for good. Luckily, Lorne learns about his true plans when Wesley hums a lullaby to Connor, but before he can do anything, Wesley knocks him unconscious and takes off with the baby.
However, things don't work out as planned for him. Justine, determined to deliver the child to Holtz attacks Wesley and slits his throat, leaving him on the street to die and taking Connor.
Finally, having Angel's child in his possession, Holtz intends to execute his plan, but things don't happen quite that way. He is pushed with his back to the wall by Wolfram&Hart *and* Sahjhan, both want the child for reasons of their own. Originally planning to take Connor with him away to another country, he has to drop that plan and the only escape appears to be a hellish dimension. With the baby in his arms and surrounded, he jumps through the deadly portal, to the astonished eyes of almost everyone present. Angel attempts to jump after him, but he's too late and the portal closes and vanishes. He remains lying on the ground, staring teary-eyed at the spot where the path opened and only manages to speak one word - "Connor".