Jennifer Lopez got down and dirty with co-star Alex McLoughlin while filming The Back Up Plan on Tuesday.

The grimy pair shared a passionate kiss, under the watchful eye of Jen's real-life husband Marc Anthony who was visiting the New York set.

In another scene, Jen fussed over one of the tiny actors playing her twins in the movie.

The actress was a natural with the babies – and so she should be with her own twins – Max and Emme – at home.