...they kill Jaws. The blood in the water attracts a large group of average sized tiger sharks. The men who survived are now picked to pieces, die slowly and very painfully.
Dawn of the Dead
...the remaining survivors fight back successfully and all the zombies are killed. The remaining population of humans, so small in size, breeds to replenish the earth but because the gene pool is so limited, all the offspring develop horrible abnormalities and extreme health problem, weakening the species further, until they all die out any way.
Return of the Jedi
...the Empire infects Endor with a virus, the Ewoks go totally feral, biting everyone and infecting them with Rage. The whole of Endor turns into 28 Days Later; bloodthirsty Ewoks ravage the moon hungry for flesh. The Empire uses trained Jedi to mind control them and sends the killer Ewoks out to take over the galaxy. Everyone still hates the Empire and now, the Ewoks too.
Leaving Las Vegas
....Nicholas Cage is convinced to go to rehab and sobers up. After realizing he is in love with a prostitute and she is pregnant with his baby, he opens up a vein in a hotel bathroom. Because of the repeated attempts at his life, he is committed to a mental institution where he remains for the next 20 years on heavy sedatives. Meanwhile Elisabeth Shue has his baby, it grows up without a father present and a mother who is still hooking. The child eventually becomes a Meth dealer. When Nick is finally released, his son, angry, hooks him on Meth purposely and then guts him like a fish, literally, during a ten day no sleep paranoia fueled drug haze.
...it's not a dream and Tom Cruise is just schizophrenic. He has killed Penelope Cruz. The put him on trial for murder. Convicted and given the death penalty by lethal injection. Jason Lee shows up to witness his death.
Lord of the Rings
...Frodo totally fails. Sauron gets the ring back, and leading the orcs, they take over Middle Earth. Unchallenged, Sauron then turns on all the orcs killing them. Bored, he feels lonely. Wishes for friends. Doesn't even have a dog to keep him company. Regrets his choices. Cries a lot by himself lavaside. Develops lung cancer from hanging around too much volcanic ash. Sad.
...Crime bosses are brought to justice once in the courtroom - life sentences for all. Joe Pesci kills Robert De Niro, then Sharon Stone, picked up by the cops for both, sentenced to life. Bosses and Pesci all join the prison choir after turning their lives over to Christ. Become famous and put out a CD of their music. Give inner city turn your life around speeches about the dangers of trusting the Mob and gangs. Las Vegas Casinos continue to rape everyone of their money for the next 300 billion years.