This alien mask looks like it's straight out of Area 51. The typical grey alien look with oversized black eyes is what many will expect to see once they are inside Area 51. Give them a spook when you wear this outside the facility on your way to storm inside.

Smuggle aliens out with this simple costume t-shirt that will fool even the most skeptical of observers. This funny shirt reads "This is my human costume I'm really an alien" in all capital letters.

Blend in with the aliens when you storm Area 51 wearing this funny full bodysuit made of polyester lycra and spandex. This is a full coverage unisex suit available in sizes from Small to XXX-Large.

Bring a little buddy inside Area 51 with you as you storm the place. This cute little grey alien sits on your shoulder, looking normal and blending in. The alien stays on your shoulder via a clip.

This funny logo t-shirt looks like a souvenir from the event. The graphic has a human woman split in half to reveal an alien inside. The slogan around the image reads "Storm Area 51 See Them Aliens" in all caps.

Look like a real Area 51 VIP when you add this lanyard with official-looking Area 51 access badge. The ID pass comes complete with a barcode and official-looking badge number.

How crazy would it be to storm Area 51 with your powerful giant alien friend? Or to make it look like you're being abducted RIGHT THERE IN PLAIN SIGHT? This funny inflatable costume makes it look like you're being carried by a big green alien. The costume stays inflated with an onboard fan.

Use these sunglasses to mimic the typical pop culture grey alien look. The glasses look like they should be covering up eyes in an elongated diagonal vertical shape familiar in movies, tv shows, and comics.

These fun circle glasses come in light shades and are inspired by a look made famous by John Lennon. The round frame glasses come in a three-pack so you can pick the color (blue, pink, or purple) that suits your mood or outfit.

These fun glasses have a lot going on. They are a cyclops style that can be used to cosplay characters from sci-fi including Geordi LaForge from Star Trek or robots. These glasses have a mirror lens. Shown here in black, they are also available in different frame colors with a lens in different shades.

These fun costume sunglasses have a honeycomb segments look to them, making you look like you've got insect eyes! A really simple costume would add these to an antennae headband for a quick and easy bug outfit.

Wear these to keep haters at bay. These meme-ready sunglasses come in a variety three-pack so you can go insta-crazy with your besties. They'll help you deal with everything that comes at you.

Get this 12-pack of sunglasses with heart-shaped lenses for your next summer beach party or other fun event. They are also great for bachelor (stag) or bachelorette (hen) parties, summer weddings, and other outdoor parties. Shown here in black, these are also available in blue, green, pink, leopard print, orange, lilac, red, white, and yellow. You can also get a variety pack of different colors.

Topping our list were several pieces that can be used for different styles of DIY costumes. This cloak can be used as the basis for several different costumes, including horror priest or monk, wizard, witch, and more. This one is available in several different colors, including white, red, blue, and black. Shown here is the best-selling color: coffee.

These puffy pants are available in a variety of colors and can be the centerpiece for a variety of different DIY costume ideas. Get a pair of these comfortable pants for your belly dancer costume, Aladdin or Genie (or Jeannie) outfit, or other Arabian or Middle Eastern style costume.

A bee costume accessory set like this one was a best-seller last year. This set includes a black and yellow tutu skirt, bee headband with antennae, bee wings, bug-eye sunglasses, and fun striped socks. Wear with a black top or leotard for a complete costume.

An easy multi-use eye mask like this one was another best seller in 2018. It's a soft and comfortable mask that can be worn with the purple side out or the blue side out. This is a great accessory for a dress-up play chest or to use in a pinch for a superhero costume.

This complete martial arts-style anime character costume comes with the cosplay vest, t-shirt, black pants, black gloves, and white armors for the arms.

Arabian style was popular in 2018. This boys Arabian prince costume was another best-seller. The luxe-looking costume comes with the trimmed shirt, yellow pants, matching belt, and stylish green hat.

This is an easy mermaid costume t-shirt dress with a sharp two-sided print. The photorealistic print looks like a sexy mermaid wearing a seashell bra. This fun costume dress also makes a great cover-up for the beach.

The Arabian theme continues with this best-seller from 2018: a girls Belly Dancer princess costume. A fun and pretty costume dress just like this one topped our list last year.

Fire-fighter costumes were popular last year too, with the final two best-sellers coming from the category. First we have this accessory set that will fit most kids -- it's a bold red firefighter vest and matching Fire Chief costume hat.

Finally to round out our top list of costume sales from 2018 is this full uniform fireman costume for kids. This is a realistic outfit consisting of bib overall pants and a matching jacket. The costume has working zippers and pockets, reinforced knee and elbow patches, and other authentic details.