[5][6] Chad Lee is a martial artist and aquatic performer who was chosen to serve as the Blue Lightspeed Ranger.
[7] Kelsey is a free-spirited and quick-witted yet impulsive and hot-headed professional mountain climber and extreme sports enthusiast who was chosen to serve as the Yellow Lightspeed Ranger.
[8] As a child, the Mitchells were involved in an accident wherein Ryan was almost killed before he was saved by a demon called Diabolico, who held him prisoner until his 20th birthday.
The demons are monsters who sought to conquer Earth five millennia prior to the series, only to be sealed by a powerful warlock.
Upon learning the city of Mariner Bay was built over their former castle, they work to destroy it and revive their leader Queen Bansheera to seek revenge on humanity, only to face opposition from the Lightspeed Rangers.
[14][15] In response, Diabolico attempts to use Carter Grayson to kill Bansheera, but is captured by Olympius, brainwashed by the demoness, and forced to serve her son.
Subsequently, Bansheera resurrects Diabolico and Olympius as super demons to weaken the Rangers, who narrowly kill them once more.
Loki (pronounced "Low-kai") is a fierce and loyal kobold-themed demon warrior, friend of Diabolico and Vypra, and the strongest of Bansheera's generals.
Despite his newfound power and developing a rivalry with Carter Grayson however, he proves less adept than Diabolico and loses his position to Loki.
[12][21][22] Following Bansheera's resurrection, Olympius mounts failed attempts at winning her affection and eliminating Vypra and Loki before they can usurp him as her second-in-command.
Upon escaping the Shadow World, Olympius wreaks havoc on Mariner Bay until Angela Fairweather severs his connection to the technology, allowing the Rangers to defeat him and destroy the Star Power.
Queen Bansheera is a demoness monarch who was initially absent following the demons' release before eventually joining them in an energy form.