Can you finish this line? "They'll fight for freedom wherever there's trouble..."

If you have the G.I. Joe theme song running through your head now (you're welcome, by the way), then chances are you grew up in the 1980s.  With constant reboots of classic '80s movies and television, not to mention the setting of the hit Netflix show, "Stranger Things," 1980s nostalgia is going Hulkamania and running wild on you.

Back in the old days, most collectors didn't think much of the comic adaptations of the cartoons. Given the present trends, how collectible are these artifacts of 1980's pop culture?

G.I. JOE: A REAL AMERICAN HERO #1

G.I. Joe has been around since the World War II era of comics, but it wasn't until 1982 that Marvel Comics was given the task of reinventing the brand. What was created was a science-fiction infused action cartoon that holds a dear place in the hearts of millions. In the 36 years that have followed, there are more action figures, comic series, and movies than I care to count...and the number continues to expand. And it began with the limited series, G.I. Joe: A Real American Hero.

This landmark issue is quite the collectible comic in high grade. Near-mint 9.8 graded copies have steadily risen in value over the past two years. Back in 2016, that 9.8 averaged $225 over 24 recorded eBay sales. Last year, that same G.I. Joe: RAH #1 sold 46 times and averaged $242. The popularity is continuing to build, and the 90-day average is presently at $272.

TRANSFORMERS #1

Hasbro's other iconic line of action figures had a resurgence in 2007 when Michael Bay brought the Transformers to life for the big screen. Nine years later, the franchise is on its sixth movie, including the Bumblebee spin-off, with more to come. Marvel was initially given the task of creating the Transformers character bios and story in order to sell toys, and the company published the first comic appearance of the characters in 1984's Transformers #1.

Last year, a graded 9.8 boasted a fair market value of $371. Other near-mint copies are still bringing the triple digits, but there is a noticeable drop off from a 9.8 to a 9.6 - a $255 drop off, to be precise. A 9.4 dips below the $100 mark and averaged $82 in 2017.  In fact, anything below an 8.5 has an FMV below $50, so if you're looking to invest, you'll want to aim high.

MASTERS OF THE UNIVERSE #1

DC Comics had their own toy line tie-in in the '80s: Masters of the Universe. In 1982, DC published a three-issue limited series featuring Mattel's new characters, most notably the generically-named He-Man.  Besides numerous comic titles, the muscle-bound prince of Eternia has spawned a movie - albeit a horrible one that starred Dolph Lundgren as He-Man and Frank Langella as Skeletor (who was in charge of casting for that one?) - six action figure lines, and four cartoon shows. There's a Masters of the Universe film reboot that's been in the works for some time now, and it's questionable whether or not that will ever see the light of day.

Still, good ol' He-Man has been making a comeback lately, although mostly through tongue-in-cheek humor. Robot Chicken poked fun at the cliches of the show, particularly those involving Skeletor. There's also the "What's Goin' On?" dance remix starring He-Man.

If a new movie does get made, Masters of the Universe #1 (1982) will see a spike. For the past two years, a CGC 9.8 has stayed in the $125 range. A good movie trailer will definitely capture the attention of many He-fans, and that $125 could quickly jump in that event.