In the middle of March 2009, Liam Neeson interrupted filming his scenes in order to visit his wife Natasha Richardson in the hospital after she had a skiing accident. The brain injury she received from this accident led to her death a few days later. Just a few days after her death, Neeson voluntarily returned to the set and completed his performance. The filmmakers changed the script accordingly, and Neeson completed his performance in two days.
Screenwriter Erin Cressida Wilson wrote the part of Catherine specifically with Julianne Moore in mind.
This film was solely financed by the French company StudioCanal, which had entirely recouped this film's budget via international pre-sales (before this film's first festival screening).
Shot over a period of 37 days in Toronto.