Invitation is a 1952 melodrama starring Van Johnson and Dorothy McGuire as a happily married couple, until the wife learns a secret about her husband. The film was based on the short story "R.S.V.P." by Jerome Weidman.
Ellen Pierce (Dorothy McGuire) is very happily married to architect Dan (Van Johnson). However, due to a bout of rheumatic fever in her childhood, her heart is weak and she cannot exert herself too much; how frail she is, she does not really know. Her wealthy father (Louis Calhern) and the family doctor (Ray Collins) have kept from her the fact that she probably only has a few more months to live.
When Ellen visits acquaintance Maud Redwick (Ruth Roman), Dan's embittered former girlfriend, Maud reminds her about a vicious remark she had made at Ellen and Dan's wedding that he was only a "loan" for about a year. That, plus an invitation addressed to Dan to a medical conference and various other clues, leads Ellen to discover the truth, not only about her prognosis, but also an even more devastating secret: that her father had arranged the marriage to make her happy, and that Dan did not love her.
When Dan finds out, he confesses via flashbacks that he had initially
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