'The Big Bang Theory' recap: Trouble in Paradise?

Leonard (Johnny Galecki) and Penny (Kaley Cuoco-Sweeting) try to prove Sheldon wrong after he says that he and Amy are a 'superior couple' on 'The Big Bang Theory' (Michael Yarish/Warner Bros. Entertainment Inc.) (�© 2014 WBEI. All rights reserved.)

Leonard and Penny may be engaged, but they aren’t living happily ever after just yet. The couple end up on a double date with Amy and Sheldon, who is making up for the contractually obligated “date nights” he missed out on while on his trip. The date turns competitive however, when Sheldon states that he and Amy have a better relationship than Leonard and Penny (as well as Penny and Chardonnay).

Leonard challenges Sheldon, insisting something as complicated as a relationship couldn’t be ranked, leading Sheldon to counter with a compatibility test that he and Amy scored high on. He challenges the duo to take it themselves, but Penny refuses and leaves the table in a huff.

Leonard follows his fiancee, who confesses that she is feeling scared about spending the rest of her life with someone who is so different from her. Leonard confesses that he’s scared about getting married too, which does nothing to soothe Penny.

“You being blindly infatuated with me was the rock we were building this relationship on!” Penny exclaims.

“You’re scared, I’m scared,” Leonard says. “But it doesn’t make me not want to do it. It just makes me want to hold your hand and do it with you.”

That’s enough to convince Penny that opposites do attract! Even Amy swoons after hearing Leonard's assurances, although Sheldon is less than impressed.

Also having some confidence issues is Howard, who has been asked by NASA to throw out the first pitch at the Angels game. When Wii baseball and a strong high five proves to be too much for his arm to handle, Howard realizes he’s in over his head. Bernadette and Raj work to help Howard prepare, though Raj proves to be a better heckler than a coach.

Knowing he will never get a ball to reach home plate alone, Howard chooses to enlist the help of a Mars Rover prototype the day of the game. The unveiling leads to cheers from the crowd, as well as from his friends who have all shown up to support him. The excitement is short-lived however, as the rover moves at a snails pace across the field.

The crowds' cheers turn to boos, with Raj and Sheldon loudest of all. With friends like them, who needs enemies?