This Halloween could be a howling good time for pet costume retailers.

More than 31 million people will be dressing their pets in costumes this year, according to a report issued by the National Retail Federation and Prosper Insights, which surveyed 6,961 consumers.

And they are projected to spend around $480 million on little doggie (and kitty) outfits, which translates into roughly 4 percent growth from last year.

The biggest question here is: what should Murphy and MacGyver be?!