The episode largely takes place on the holodeck, which is running a holo-program in black and white instead of the usual color.
During an episode of The Adventures of Captain Proton on the holodeck in a recurring Voyager hologram program in the style of vintage movie serials such as Flash Gordon and Buck Rogers, Ensigns Tom Paris and Harry Kim are forced to leave the program running when spatial distortions trap the ship and disrupt their control over the computer.
They are detected and attacked by Dr. Chaotica, who believes them to be from the fifth dimension, and whose holographic (photonic) weaponry — though harmless to humans — is deadly to the aliens.
Inside the program and in full costume, Janeway/Queen Arachnia uses her charms to manipulate Chaotica into lowering the "lightning shield" protecting his fortress under the pretence that her loyal subjects in their "spider ships" can attend their wedding.
She then deactivates the lightning shield enabling Captain Proton to fire his "destructo beam" at Chaotica and defeat him, thereby freeing Voyager and allowing ship and crew to continue on their journey home.
[9] On November 9, 2004, this episode was released as part of the season 5 DVD box set of Star Trek: Voyager.