Episode 73 of "Angel"
s04e07 Apocalypse, Nowish

Angel and company brace for the imminent arrival of a hellish beast and toil to stave off Judgment Day. Although the creature's coming was initially revealed through Cordelia, she is unable to dredge up the ghastly specifics about the otherworldly visitor from her spotty memory. Only one thing is certain - the demon will bring about the end of the world if no one stops it. With no other choice, Angel partners with Lilah to fight the common threat. Meanwhile, Fred and Gunn get sidetracked by a bump in their relationship. Cordy and Connor, on the other hand, pair up to hunt down the menace themselves.