Bay City Defenders

In the year 3000 humankind has evolved into a utopia where a police organization called Galactic Union Police has tracked down every single criminal - except for -, who hijacks a prison full of cryogenically frozen convicts and escapes to the year 1998 in the hopes of altering the course of history, but not before fatally striking down the Galactic Union Sargent, Amber Dalton. The four Galactic Union officers responsible for -'s escape, including Amber's fiance, John Harper, pursue him through time and end up in the fictional town of Bay City, where they are acquainted with the 21st century by Emma Stanford, the daughter of a rich industrialist and a dead ringer for Amber, due to him being Amber's distant, but still direct, ancestor. Despite John's initial reluctance, Emma eventually joins the team as the ally and helps them blend in the late 90's. The GUP officers both defend Bay City from the onslaught of -'s Mutants and attempt to keep the original timeline from drastically altering.

Due to Emma' estrangement from her father and the fact he never had time for her, the GUP officers instead move into an abandoned clock tower in the middle of the city and begin operating a business named A Nick of Time Odd Jobs in order to get by. Emma soon finds that her father's overbearing determination to have her follow his footsteps and take over his company has become too much for her to bear, and she abandons her father to go live with the other officer in the clock tower. Over time, John and Emma's relationship also blossoms and they begin to catch feelings for each other, although neither has the gall to admit it to the other.

Emma soon discovers that -'s deep-rooted hatred for humans is a manifestation of his origin as a horribly disfigured mutant shunned by the rest of the genetically perfect population. - displays extremely impressive combat skills throughout the season, but his biggest weakness is his constant need to take a vial of special serum in order to prevent turning into a mutant permanently. Emma notes -'s potential capacity for kindness, such as his affable treatment of his daughter, Vira, but the rest of the Galactic Union officers are fully committed to bringing in - at all costs.

The Rangers' mission is complicated by the introduction of the Bay City Guardians, a new business venture by Mr. Stanford to protect customers who pay for the Guardians' services. At the same time, Mr. Stanford discovers that Wes is a Time Force Ranger and tries to offer him the position as commander of the Guardians, which Wes refuses. One of the Guardians, Dizzy Parker, a classmate of Emma from middle school, discovers the Quantum controller box, becomes the Quantum Ranger, seizes control of the Q-Rex, and is put in command by Mr. Stanford of the Silver Guardians. Long resentful of Emma's privileged position in life (and the fact that she was blamed for a practical joke in middle school that had gone awry), she remains aloof and distant from the other Rangers and operates independently of them.

Ransik's robotic underling, Frax, grows deranged and breaks away from Ransik, destroying all of his vials of serum in the process. A desperate Ransik ransacks Mr. Collins' company, Bio-Lab, to acquire their supply of newly developed serum, and in the process severely injures Mr. Collins, leaving him in critical condition. This development causes the sudden arrival of Alex, who intends to "set history straight". He resumes command as the Red Time Force Ranger, informing Wes that his father will die the next day. Alex makes a series of questionable decisions battling Frax's powerful creation, Dragontron, while a resigned Wes briefly takes over command of his father's business. The Rangers, unable to stand Alex's leadership any longer, mutiny and force him to give Wes back the Red Time Force morpher. Wes leads the Rangers to a resounding victory over Dragontron, while Alex uses technology from the future to save Mr. Collins' life. Alex returns to the future, respectful of Wes' role as the leader of Time Force.

When Vypra of Power Rangers Lightspeed Rescue lore revives a Super Demon named Quarganon, the Time Force Rangers briefly team up with their Lightspeed Rescue predecessors to take down the combined forces of Vypra, Ransik, and Quarganon.

Ransik eventually tracks down Frax and reprograms him to be his completely subservient robotic slave. Frax creates a new fighting machine, Doomtron, which rains destruction on Silver Hills and sends most of the city's infrastructure spiraling into a time-space vortex. Upon hearing from Alex that their fate was doomed, Wes forcibly returns the other four Rangers back to the year 3000 for their own safety, leaving him and Eric to try to desperately defend Silver Hills from both Doomtron and Ransik. Eric is severely injured by a slightly damaged Cyclobot, and hands the Quantum morpher over to Wes, who is the city's last hope. Alex tries to wipe the memories of the year 2001 from the four officers, but they rebel once again and choose to go back in time to help Wes - which culminates with Jen returning to Alex their engagement ring. The reunited Rangers destroy Doomtron, along with Frax, but find themselves overmatched against the awesome power of Ransik. Ransik attempts to deliver the finishing blow to Jen, but accidentally strikes Nadira, an act which horrifies him and causes him to repent. He turns himself in, and the four Time Force officers, their mission complete, return to their own time, but not before Jen and Wes finally confess their feelings to each other. Wes agrees to his father's revised proposal to become head of the Silver Guardians - who now provide their services freely - with the condition that he have Eric working alongside with him as co-commander.

A recurring theme in the series is that an individual controls his or her own destiny, as exemplified through Wes' character development - he continually refuses to adhere to the life his father has set for him as successor of the lucrative Collins business, remaining committed to traversing his own path, even when he is told by Alex that it is destiny for him to take over the company after his father's death. Other characters also fight against the currents of predetermined destiny, such as how Eric determinedly fights his way out of squalor and poverty to become head commander of the Silver Guardians, or when Jen and the other Time Force Rangers ignore the predetermined events of history and choose to return to the year 2001 and save Wes from dying. Even the penultimate clash of the season - Ransik with the Time Force Rangers - culminates with Ransik's choice to accept responsibility for his crimes and carve his own path in life anew.