Junior (Arnold Schwarzenegger and Danny DeVito)

Junior is a 1994 American science fiction comedy film directed and produced by Ivan Reitman, and starring Arnold Schwarzenegger, Danny DeVito and Emma Thompson.

Austrian research geneticist Dr. Alex Hesse and his OB/GYN colleague Dr. Larry Arbogast invent a fertility drug, "Expectane", designed to reduce the chances of a miscarriage. With the drug unapproved by the FDA, the colleagues are not authorized to test it and are unable to continue their research. Noah Banes, the director of the laboratory, informs Larry that while the FDA denied human experimentation, the team has received a donation from geneticist Dr. Diana Reddin from the ovum cryogenics department. Alex plans to start over in Europe, but Larry suggests they can still perform the experiment, with Canadian firm Lyndon Pharmaceutical offering to fund them provided they find a volunteer. Alex questions the likelihood of a pregnant woman taking an unapproved drug, but Larry suggests omitting the volunteer's gender and convinces him to impregnate himself with an ovum codenamed "Junior".

That night, Alex dreams his potential offspring has his own face. As weeks go by, he complains to Larry of morning sickness and sore nipples, and chats incessantly about walks, massages, and naps. Contemplating fatherhood after watching television commercials, Alex breaks down sobbing. When the time comes for Alex to end the experiment and release the results to Lyndon Pharmaceutical, he continues taking the drug as he has decided to carry the pregnancy to term; initially annoyed, Larry agrees to keep it hidden. Alex develops a relationship with Diana, and reveals his pregnancy to Angela, Larry's ex-wife, who also happens to be pregnant by Aerosmith's personal trainer.

Diana is stunned and angry when it is revealed that the "Junior" ovum is hers, and Banes attempts to take credit for the experiment. Disguised as a woman, Alex hides in a retreat for expectant mothers, blaming his masculine appearance on anabolic steroid use. Diana visits Alex at the resort and the two reconcile, telling each other it does not matter who is pregnant because she is the mother and he is the father. Larry reveals the experiment's data to Lyndon Pharmaceutical, who agree to partner with them.