Last night's episode of Supernatural left fans sitting on the edge of their seats with one of the season's best episodes. In one last desperate shot at saving Dean {Jensen Ackles), Sam (Jared Padalecki) convinces him to track a doctor named Benton who has found the secret to eternal life. Bobby (Jim Beaver) finds out where Bela (Lauren Cohan) is hiding, which leaves Sam to deal with the crazy doctor on his own when Dean takes off to go after her.

Dr. Benton had the formula that he could have given to Sam and Dean, but he didn't. Dean wasn't going to steal vital organs from innocent people just to live forever and watch Sam get old and die.

"Supernatural" creator Eric Kripke said in a previous interview that we would learn more about Bela and her backstory. Kripke kept his word, and we learned something huge about Bela. Her parents' car accident wasn't an accident. Viewers were first led to believe that Bela killed her parents and inherited millions.

In a very surprising twist at the end, we learned the truth about Bela and why she acts the way that she does. Bela made a deal with the devil, and she had 10 years to live before the hellhounds came to get her. The reason for stealing the colt? It was the deal she made with Lilith - the little demon girl who holds both her and Dean's deal - to get her out of the contract.

Turns out that wasn't enough. Bela had to go and kill Sam. Bela was willing to kill Sam and Dean to get out of her contract, but this time, she wasn't smart enough. This time around she was out smarted by the brothers, and Dean using blow up dolls in the bed as props was priceless.

Bela could have gotten help from the brothers, especially since Dean is in the same situation as she is, but she decided to go against them and be on the wrong side. The ending was perfect. All you heard was the barking, and the screen turns black.

Is Bela really dead? Was Bela telling the truth? Who was she on the phone with? Hopefully these questions are answered in the season finale.

Between the intensity and desperation, Jensen Ackles and Lauren Cohan's acting really made the episode stand out.

Next week's season finale will leave "Supernatural" fans sitting on the edge of their seats. Dean's time is up. Will he survive? Guess we'll have to tune in and see. Do you have any thoughts on Bela and her deal with Lilith or just the show in general? Share them with us!

Story by Angie Rentmeester
Starpulse.com contributing writer