Brilliant with bad ending.
Freddy's been gone and forgotten by the people of Springfield; his power is the fear of teenagers, so Freddy found a way to bring the fear back by searching the bowel of hell. He found Jason as a perfect role to be his puppet, except he, Freddy, does not know everything about him.
Once Jason get revived, he won't stop, nor get turned off, especially when Jason thought his mother is actually gave him a task to scare those teenagers on the Elm Street that was disguised by Freddy. Freddy's biggest mistake is lack knowing about Jason's personally, so he didn't mentioned to him that he is required to "kill only fews and go back to his graveyard" in which it doesn't work that way.
With all of bodies piled up, teenagers are starting to run out, Freddy haven't got his power back. So, he blames on Jason instead of himself, and he somehow, got into one of stoner's body and uses tranquillizer medicine to knock out Jason, in which it doesn't make any sense since Jason is undead.
Once Jason is slept, he entered Freddy's Dream world and learnt that his mother didn't gave him these tasks. Freddy kept attempting to kill Jason and failed repeatedly. Kinda odd that Jason is actually superhuman undead in Freddy's world. Later, Freddy learnt that Jason is scare of water, which is also odd that Jason doesn't have feeling and he was in water many time in other Friday the 13th series.
On the way to Crystal Lake, the teenagers who carried Jason's sleeping body in back of the van, for some reason, believes Jason should've go back his home like it'll end on his killing spree or whatever; yup, it still doesn't work that way.
After Jason woke up, he continued on terrorizing those teenagers whose had a feeling for him and wanna to help bringing him back home; stupid teenagers, right?
Freddy was moving on to different task by trying to kill this girl, who was trying to save Jason in Freddy's world, so that way Freddy can get his power back and...... he failed! Again! He's so freaking lousy.
The girl work up and brought Freddy into the real world. Bang! Freddy Vs. Jason battle got started. What the heck is that? Jason bleed? Jason can feels pain? Jason's both eyes got stabs to blind and still able to see? Jason fails to use counterattack that was wide open in front of him?
Few beats up on Freddy and he got weak? Freddy is mastered in Kung Fu?
The battle is ridiculous, but somehow enjoyable.
Jason won by kills more, taking a lot of beating and still standing up, refuse to die, and he's always came back.
Freddy lost for failing to bring his power back, only kill one, got weak fast, got hated by everyone, and lost the fight.
One more odd is that Jason carry Freddy's head for some reason, and his winking at the end to cheer up the fan of Nightmares on Elm Street for being a loser. Ha ha.