Penny and Sheldon will play an experiment they devised that supposedly makes people fall in love, according to "The Big Bang Theory" season 8, episode 16 spoilers. Meanwhile, the urn containing the ashes of Howard's mother goes missing at the airport.

The gang tries an experiment over an article that Amy has read that suggested that two random people can fall in love in "an accelerated time frame." They all decided to see if the hypothesis is true. Penny doubts that Sheldon will tell the truth when prodded for personal questions.

As they head to Penny's apartment, Sheldon tells her that if the experiment is indeed true and they fall in love, she should drive her to Dungeons and Dragons convention, to which she agrees.

"For the final part of the experiment, Penny and Sheldon then stare into each other's eyes. They are supposed to keep eye contact for a full four minutes and both struggle with this," said the spoiler.

Penny then tells Sheldon that they can stop since she only looks at him as a little brother. Sheldon doesn't disagree with that sentiment.

Meanwhile, Howard loses his bag at the airport which contains her mother's ashes.

Bernadette threatens the attendant: "You'd better find my husband's mother because either way, we're walking out of this airport with a dead woman."

Fortunately, the airport finds the bag and Howard says that he won't let the urn out of his sight ever again. Bernadette now is worried that it would be placed on their bedroom.

The synopsis offers plenty of spoilers for "The Big Bang Theory" season 8, episode 16: "As a joke, Sheldon and Penny try an experiment designed to make participants fall in love. Also, Leonard, Amy, Raj and Emily spend the evening trying to escape a room with a "zombie." And, after returning from Mrs. Wolowitz' funeral, Bernadette and Howard run into trouble at the airport."

Stay tuned for more "The Big Bang Theory" season 8, episode 16 spoilers ahead of the airing date on Feb. 26 on CBS.