A trio of brilliant performances and an intelligent, realistic screenplay make this a very good film.
Annette Bening & Julianne Moore play a married lesbian couple whose kids want to discover who their surrogate father is. They secretly meet him (Mark Ruffalo) and he interlopes in the close family unit, much to the chagrin of Annette Bening's character.
There's been a few movies which have explored this type of theme in the past but they come across more as plots for a sitcom (Made In America a prime example), this balances the scales of comedy and drama perfectly.
Annette Bening is absolute brilliant in this. A career best performance and any other year she would have won the Best Actress Oscar (or even the Best Supporting Actress award had the producers campaigned her there).
A highly recommended watch.