Its purpose is to cure baldness by growing hair, which Naldo plans on using to grow chest hair. Barry and Naldo leave for a second. Cyd opens an ice chest to get food, but instead a beaker filled with Naldo's homemade hair gel comes out, she bumps into the laser and activates it, and then it gives them the power to time travel.
Barry and Naldo try to recreate time travel, but fail over 232 times. Bret and Chet came in and caused a disaster that messed up Barry's eyebrows.
In this episode, it has no real importance. Shelby just points at it in an alternate timeline.
Barry planned on shooting the laser at Cyd's and Shelby's tachyon signatures to create a wormhole to 1978. However, he fails to do so because the signatures faded away. They caught a small bit of the tachyon particles however.
Barry uses the laser to teleport the girls to the New York City Spooktacular. Things didn't go as planned though, the laser turned them into "ghosts". They couldn't touch each other to time travel back to Portland. When they eventually figured out away to go back, (Possession of Lucas and Riley) they time travel to the moment that Barry said he invented teleportation. They attempt to smash the laser with hammers, but to no avail.
- It is interesting to note that, although at a low setting the laser can cause damage to a human, a higher setting appears to have no effect (unless it first reacts with the unknown material).