Funny comic actors don't always get a Judd Apatow movie to star in -- sometimes they have to settle for small fare like I'll Believe You. Get a handful of them together, and a movie like I'll Believe You can end up being more fun than it probably should have been. Writer-director Paul Francis Sullivan's first feature has a reasonably cute premise involving a late-night radio show for conspiracy theory wackos, in which a genuine conspiracy -- involving aliens -- seems on the verge of being uncovered. But the film would strictly be small potatoes if it weren't for a handful of likable comics contributing their talents, including Patrick Warburton, Chris Elliott, Ed Helms, Fred Willard, and most surprisingly, Thomas Gibson, who played it straight on both Dharma & Greg and Criminal Minds. Some of these roles amount to little more than glorified cameos, but they do give the project enough comic credibility to make it more widely visible than its modest means would have otherwise allowed. Sullivan's script should also be credited for defying expectations in interesting ways, namely, by not actually being about what it says it's about -- and by making that twist unobtrusive enough and clever enough that it earns the right not to be spoiled in a review. Slight but amiable, I'll Believe You is worth a look if you like the comic actors listed above, and if you think a low-budget comedy about UFOs -- or possibly something else -- sounds like a good time.