Power Rangers Time Force: Dawn of Destiny (2002)

Locked in a fierce battle with Venomark, the Rangers are bitten by the venomous mutant...except for Wes, the Red Ranger, who runs to his father's lab for the antitoxin. Saved by the serum, the Rangers, Q-Rex and Shadow Force Blue defeat the vicious Venomark. Jen, warns Wes that his Dad's serum must be destroyed or the future could be in danger of shifting. But Mr. Collins refuses. It's too profitable to give up, he says. Desperate for the antivenom, Ransik and his mutant Severax attack Bio-Lab and unbeknownst to Wes, they severely injure his father. Suddenly, a mysterious figure from the future appears and the Rangers are stunned to see it's Alex, the original Red Ranger. They thought he was dead - killed by Ransik. The future has shifted, he says, and he has been sent back to fix it.