In the movie DR is 17 and DP is supposedly about 35 (but looks 55). So he agrees to watch her over Christmas for 2 cops.. (ok suspend disbelief)... he's reminded she's underage. It starts out more like father daughter stuff then she falls for him. In an effort to make his fiancé Ann Francis jealous and get some good writing material they marry. This is when I hit pause to look up DR real age which is 22. I felt a bit creeped out if she was really 17. Glenda Farrell plays the old lady which is ironic since she's closer to Dick Powell's age.
Anyway the acting is good and DR is adorable. I won't give too much away but it's not for everyone.
Review of Susan Slept Here
