Synopsis

When a woman tells two former lovers that each is the father of her runaway teenage son, uptight lawyer Jack Lawrence and eccentric writer Dale Putley separately begin searching for the boy. After discovering they have been given the same story, the mismatched pair join forces, following the teenager across California while trying to bring him home and determine who his real father is.

Factoids & Trivia

• The film is an American remake of Francis Veber's 1983 French comedy Les Compères, also known as ComDads.

• Robin Williams and Billy Crystal had already developed a popular comedy partnership through their work on HBO's Comic Relief. Their only previous film together, Hamlet (1996), featured them in separate scenes.

• The concert sequence featuring Sugar Ray was filmed in a Los Angeles park over three days. Extras were required to cheer and move energetically to the same song throughout the shoot, making it increasingly difficult to maintain the crowd's initial enthusiasm.

• During a break from filming the concert, Robin Williams reportedly entertained extras in the bleachers.

• Williams and Crystal made guest appearances as their Fathers' Day characters on the Friends episode "The One with the Ultimate Fighting Champion" as part of the film's Warner Bros. promotional campaign.

• The movie was filmed between July 8 and October 9, 1996, at locations including Los Angeles City Hall, Treasure Island in San Francisco Bay, and Reno/Tahoe International Airport.

• In South Africa, the film was released under the title What's Up Pop's?. The title was later changed to What's Up Pops? for home video after the studio noticed the apostrophe error.

• Made on an estimated $85 million budget, the film earned about $35.7 million worldwide and is generally regarded as a commercial disappointment.