Once a Ranger

"Once a Ranger" is a special two-part team-up episode of Power Rangers: Operation Overdrive, commemorating the fifteenth season of the popular Power Rangers television series begun in 1993. It features the return of five former Rangers who aid the current team of Operation Overdrive Rangers against the son of the original two villains of the series.

Plot Summary
Thrax, the son of Rita Repulsa and Lord Zedd arrives and proposes a temporary alliance with the four factions of Operation Overdrive villains. The villains, hesitant at first, join forces and wage an all out war against the Rangers. United, the villains defeat the Overdrive Rangers. Then, as the final attack, Thrax severs their link to the Universal Morphing Grid, stripping them of their powers and making it impossible for Andrew Hartford to restore them. Sentinel Knight's spirit arrives and whisks the Rangers to safety, then he calls upon Adam Park, Tori Hanson, Kira Ford, Bridge Carson, and Xander Bly to replace the current Ranger team. They arrived when the current Ranger team tried to use their special abilities to fight Kamdor and Mig. When Adam returns to Operation Overdrive headquarters, Andrew Hartford reinforces the Morphing Grid so Thrax does not take away Adam, Bridge, Xander, Kira, and Tori's powers away as well. Five of the Overdrive Rangers feel left out and decide to leave Operation Overdrive to return to their normal lives, as they were before they became Rangers.

Mack stays, but without his Ranger powers, his role in the operation is reduced. Adam leaves with the other previous Rangers to bring Alpha 6 to repair the Operation Overdrive link to the Morphing Grid. Meanwhile, Mack learns of the legend of Excelsior -- a golden sword and the only weapon capable of fully restoring the Sentinel Knight. He decides to go and retrieve it, stopping for information from Rose at her university. When Rose intuits what Mack is doing, she gathers the rest of the Overdrive team to follow (which wasn't difficult, as none of the Overdrive Rangers were happy with civilian life). Successfully retrieving the sword from beneath Thrax's fingertips results in the destruction of a powerful monster attacking the city. After restoration of the Overdrive Rangers' powers, due to Alpha Six's successful repair of the connection to the Morphing Grid, there is a climactic final battle between both team of Rangers and their enemies. The Sentinel Knight, restored to full power thanks to Excelsior, joins them. The temporary alliance shared by the villains is dissolved as Thrax is destroyed by the repowered Sentinel Knight.

Returning Power Rangers
Four former Rangers (and one current Ranger from the future) return for this episode:
 * Adam Park: The second Black Ranger of Mighty Morphin Power Rangers, portrayed by Johnny Yong Bosch. Adam uses his Power Axe as his primary weapon.  However, he also uses the Defender Vest, the Hovertek Cycle and the Flash Point Megazord.  He serves as leader of the "Retro Rangers".  Adam had also served as Zeo Ranger IV - Green in Power Rangers: Zeo and the first Green Turbo Ranger in Power Rangers: Turbo.  After his term as a Power Ranger, Adam opened a martial arts dojo in Angel Grove.
 * Tori Hanson: The Blue Wind Ranger of Power Rangers: Ninja Storm, portrayed by Sally Martin. At the close of Ninja Storm, Tori became the sensei at the Wind Ninja Academy of students who were proficient in water techniques.  She has since opened a surf shop as she is also a professional surfer.
 * Kira Ford: The Yellow Dino Ranger of Power Rangers: Dino Thunder, portrayed by Emma Lahana. At the end of Dino Thunder, Kira had proceeded in her singing career.  She is currently working on her first album.
 * Bridge Carson: The S.P.D. Red Ranger of Power Rangers: S.P.D., portrayed by Matt Austin. Bridge was originally the Green Ranger in S.P.D. but he was promoted to Blue Ranger when Jack Landors left S.P.D. and the Red Ranger position was taken by Sky Tate.  Later, Fowler Birdie would retire as Supreme Commander of Space Patrol Delta and Doggie Cruger would take over his position, prompting a promotion for Sky to Commander of S.P.D. Earth and Bridge to the position of S.P.D. Red Ranger.  It is unknown if Sky was given the Shadow Ranger powers, or if new Rangers were selected for the Blue & Green positions.  As S.P.D. is set in the future, he has come back in time as well.
 * Xander Bly: The Green Mystic Ranger of Power Rangers: Mystic Force, portrayed by Richard Brancatisano. As of the end of Mystic Force, Xander is the manager of the Rockporium, a record shop in Briarwood where all of the Mystic Rangers had worked.