Oscar was in Rosarito with his family celebrating his wedding at the hotel, despite the rumors and stories of the outbreak threatening to close the border. As the guests enjoyed the party, he was called to the dance floor to dance with his newlywed wife Jessica, despite Jessica's parents debating whether they should leave Mexico. After his dance with Jessica, Charles Stowe is called to the dance floor for the father-daughter dance, in which he asks Ilene for a dance. However, during the dance Charles suffered a heart attack and reanimated, taking a bite out of Jessica's cheek as she tried to perform CPR. As panic ensued in the ballroom, Elena locked everyone inside in an effort to contain the situation.
A month later, it is revealed that Oscar's group survived ballroom incident with several other wedding guests. They corner Elena and Alicia outside the bar in order to get the master keys to the hotel. They are successful in retrieving the keys, but are attacked by zombies released from the bar by Alicia.
Oscar is first seen on his balcony as Madison attempts to negotiate with the wedding guests. He listens to Madison as she tries to convince his group that everyone needs to work together in order to secure the hotel and survive. Later, as the survivors lure the zombies out of the hotel, he watches from his balcony with Ilene. That night, as the survivors have a dinner to celebrate their new unity, he is on the 17th floor outside the honeymoon suite, standing guard. He refuses to let his undead wife, who is behind held inside the room, to be put down. However, Victor Strand and Oscar have a talk about love and is convinced to allow Strand to put Jessica down.
Oscar and Andrés are out at the front gates of the hotel standing guard with Madison, Alicia, Hector and Elena as dozens of refugees beg to be let in.
When Travis is beating Brandon and Derek to death, Oscar attempts to unlock the door and stop Travis. When he attempts to enter, Travis slams the door on his head to stop him from interfering so he can continue to brutally beat Brandon and Derek.
A seriously injured and unconscious Oscar is taken by Andrés for treatment. Oscar's brain begins to swell, forcing Andrés to cut open his skull to relieve the pressure. However, Oscar dies of his injuries, forcing Andrés to stab him in the brain to prevent reanimation. Oscar's death along with those of Brandon and Derek force Madison, Alicia and Travis to flee the hotel, but not before an attempt at revenge leads to the death of Andrés as well.