Colin and Greg Strause are brothers who have worked together as visual-effects technicians on dozens of movies, so you’d think that a movie they co-directed would, if nothing else, have cool special effects. Yet here’s “Skyline,” a “Cloverfield”-meets-“Independence Day” dud with laughable early-’90s technology and an even more laughable screenplay (written by some other visual-effects guys). To get digital effects that are even passable, you have to spend more money than the Strauses had available to them. The lesson: If you’re on a shoestring budget, maybe you shouldn’t make a movie about alien invaders. Or at least not one where you actually have to show the aliens.

It’s set almost entirely in and around a swanky condo in Los Angeles. This is the home of Terry (Donald Faison), who is super-buff and super-wealthy and makes his living as … a visual effects artist! Obviously. At the time of the alien invasion, he’s being visited by his seahorse-faced childhood friend, Jarrod (Eric Balfour), and Jarrod’s girlfriend, Elaine (Scottie Thompson). Terry himself has a girlfriend, the very blond Candice (Brittany Daniel), and is secretly sleeping with his assistant, Denise (Crystal Reed). They all have a super-fun party with Terry’s showbiz friends, then fall asleep in the condo, then the aliens come, the end.

Well, not quite. The alien ships hover over L.A. and suck people up into them, presumably to eat them or enslave them or whatever.

“All those people,” someone muses. “What do they want with them?”

“I’m not lookin’ to find out!” comes the reply from one of the brave-talking idiots in the group. (There are several.)

Joshua Cordes and Liam O’Donnell wrote the screenplay — the first writing credit for both — and it’s packed with intensity! “Like it or not, this is happening!” says the condo’s building manager (David Zayas), slapping some sense into a fearful tenant. “You gotta be STRONG!” About two minutes later, someone — maybe even the same person — says, “It just doesn’t seem real,” to which the manager replies, “Well, it IS real. So you better wake up!” That is the manager’s job, to tell people that what is happening is indeed real. This is a valuable service.

As mentioned, the special effects are goofy. I don’t doubt they did the very best with the resources they had, but tell that to the guy who paid $10 to see it when he could have spent the same money on a film made by competent professionals. And anyway, the effects aren’t what sinks it. That would be the flat acting, the unintentionally campy dialogue, and the unlikelihood of any audience member wanting to spend 90 minutes trapped with these particular two-dimensional imbeciles.

On the other hand, maybe the Brothers Strause are to be admired for getting this cheesy trash into theaters instead of letting it be relegated to the SyFy Channel. They’ve got moxie, anyway. And “Skyline,” while dumb and derivative and populated with completely uninteresting and unbelievable characters, at least avoids the peril of becoming boring. If this were on TV, for free, you’d totally watch some of it.

Note: Contrary to regular industry practice, this film was not screened for critics before opening.

D+ (1 hr., 32 min.; PG-13, one F-word, moderate violence, abundant cheesiness.)