Season 15

Andrew Hartford
Played by: Rod Lousich
Mack’s father and mentor to the Overdrive Rangers. It is believed he created the powers after finding the Crown of the Gods. Originally planning to be the  Red Ranger himself, he created the Overdrive powers to find the jewels of the Corona Aurora.

Played by: David Weatherley 
Spencer is the Hartfords’ butler. He has a close friendship with Mack, and gives all the Rangers advice.

Played by: Beth Allen
At first believed to be killed in a cave-in caused by the FearCats, Vella was a rescuer on the planet Mercuria with her fiancée Tyzonn.

The Sentinel Knight
Played by: Nic Sampson
After Flurious and Moltor were cursed for attempting to steal the Corona Aurora, the Sentinel Knight hid the 5 jewels around the world. Later his spirit returned to advise the Rangers on how to protect the crown.
When the Thrax, the son of Rita Repulsa and Lord Zedd returns he summoned 5 previous Rangers to take their place. He is also able to transform into the powerful Sentinel Sword and enables a merge with the Red Ranger to become the Red Sentinel Ranger.

Once A Ranger Team
Kira Ford: the Yellow Dino Thunder Ranger (Emma Lahana),  Xander Bly: the Green Mystic Ranger (Richard Brancatisano), Adam Park: the Black Mighty Morphin’ Ranger (Johnny Yong Bosch), Bridge Carson: the current Red SPD Ranger (Matt Austin) & Tori Hanson: the Blue Ninja Ranger (Sally Martin).
When the son of Rita Repulsa and Lord Zedd, Thrax, comes to Earth and blocks the Overdrive Rangers powers, the Sentinel Knight uses his powers to restore the powers of 5 former Rangers.

Alpha 6
In order to repair the broken link to the Morphin’ Grid, Adam calls upon his old buddy Alpha 6