What is it about those salacious, outrageous Lifetime movies that keep us coming back for more?

Well, for one thing, they’re kinda awesome.

Take this trailer for the new high school-thriller “Double Daddy.” The plot? Oh, just your average 17-year-old who is shocked to learn her boyfriend has impregnated a new girl at school … but even more shocked when she discovers that she too is pregnant. Cue the dramatic music.

So when Lifetime put up a poster announcing a movie called “A Deadly Adoption,” starring the comedians Kristen Wiig and Will Farrell, it got us wondering: how exactly do you pull off a spoof of yourself, without alienating your fans?

Emily Newman, art professor at Texas A&M University-Commerce, is writing a book on Lifetime. She’s a big fan.

“Most Lifetime viewers are in on the joke,” she says. “We know we are watching these movies that are ridiculous and terrible and over the top, and that’s part of the fun of it.”

Which seems to raise another important question: how do you parody a parody?

David Isaacs, professor at the USC School of Cinematic Arts and the co-head of the Comedy @SCA initiative, says the trick to pulling it off will be playing it dead on, straight ahead.

But, regardless of the quality of “A Deadly Adoption,” Lifetime has already scored, he says.

“When you are competing with so many other broadcast entities – cable, pay – this gives them an absolute promotional bonanza, I would suppose,” Isaacs says.