- "You stole a diamond?"
- ―Isabel to Max
Sometime after Tess Harding has left Earth, pregnant with Max's unborn son, Max attempts to reconcile with Liz. Walking together on a pier, Max impulsively jumps in the water and invites Liz to join him. As Liz undresses, Max is suddenly overwhelmed by images and sensations of his son crying out for him from the planet Antar. Liz jumps in to save the now-comatose Max and rushes him to Michael's apartment, where they are also joined by Isabel. Michael manages to revive Max, who is now determined to save his son.
Later, Max and Liz go to the Valenti residence and find a letter to Tess from Nasedo. In the letter, Nasedo mentions a diamond which will power the spaceship that brought the Royal Four to Earth in 1947. After more research, Liz finds a match for the diamond in the Harrington Diamond, part of a collection owned by Dolores Browning and appearing as part of a traveling exhibit in Santa Fe. Liz and Max infiltrate the exhibition disguised as servers. Max flirts with Browning, and Liz stages a scene during which Max manages to switch the alien diamond with an earthly copy.
Max learns of several secret government storage facilities where the ship might be held. He and Liz scout them out until they come to a convenience store in Salina, Utah. Armed with the knowledge that the storage facility lies under the store, Max and Liz stage a fake armed robbery to get inside. Their actions are observed by Joey, who alerts the police before himself leaving the scene. Inside, Liz waves a gun at the clerk while Max finds the secret entrance to the underground hangar. He activates the ship, but stops when he hears Liz call to him. The two escape the store with the police in hot pursuit. Max is forced to ditch the diamond, and the cops arrest them and take them to the Salina Police Station.
The next morning at West Roswell High School, Michael attempts to make a fresh start, promising Mr. Seligman that he'll attend Biology 101. Isabel arrives to ruin Michael's plans when she explains Max and Liz's arrest. Michael and Liz later arrive at the police station in Utah. Jeff and Nancy are already there, as are Philip and Diane.
- Max and Liz do a whole Bonnie & Clyde thing.
- This is the only season premiere not to feature Alex, Valenti.