Promise Her Anything

Promise Her Anything is a 1965 British romantic comedy film directed by Arthur Hiller. The screenplay by William Peter Blatty is based on a story by Arne Sultan and Marvin Worth.

Although he is an authority on children, Phillip actually despises them, so Michelle decides to keep John Thomas a secret for the time being. Unbeknownst to her, Harley is using the baby in his movies. When John Thomas is admitted to Phillips clinic for observation, Harley sneaks into his room to complete a film, but his surreptitious activities are captured by a hidden camera recording the babys behavior. Michelle is furious but, when he saves John Thomas from a potentially dangerous situation, she forgives Harley and decides he may be the better choice for a father after all.The title song, with music by Burt Bacharach and lyrics by Hal David, was performed on the soundtrack by Tom Jones. ........

Source: Wikipedia