"I love her the same way I love you"
Ethan says to his ex-wife, about his own daughter, literally right before he has sex with her....
...
- - -
Well, as they say in the tampon biz, see you next period.
The scene prior to this remark is Ethan teaching his daughter to dance. On the soundtrack, as the two dance like a romantic couple, is the song,"Make it with you" by Bread with the lyric, "And if you're wondering what this song is leading to - I want to make it with you..."
A later verse from the same song says
Life can be short or long (Ethan's life may be short if he doesn't get his experimental drug, or long if he does)
Love can be right or wrong (Paternal love for your daughter - right! 'Matrimonial' love for your daughter - wrong!)
And if I chose the one I'd like to help me through (Ethan certainly chooses his daughter)
I'd like to make it with you (Ethan would like to, er, 'make it' with his daughter...)
Don't have a go at me - I didn't put the song on the soundtrack!
And in the very next scene Ethan tells his wife, "I love her [the daughter] the same way I love you..."
And then he gives his wife a good ol' 'loving', waking up in bed with her the next morning. You can't reasonably love your daughter "the same way" you love your wife because wifely love involves physical attraction. So if you love your daughter "the same way" as you love your wife, welll....
...could it be any more explicit?
Oh, yes - and don't forget the scene where Ethan carries his daughter out of the nightclub in a fashion which surely intentionally echoes the scene in The Bodyguard where he does the same to Whitney Houston. And we all know what happened between those two in that film, don't we...?
Plus, Luc Besson has a cinematic history of similarly-orientated relationships. I'm not a huge Besson fan, but I'm thinking 'Leon' and his documentary on Serge Gainsbourg who had a... slightly unusual relationship with his daughter...
Granted, McG directed this film, but Besson wrote the thing, so he would have had major input.