Robert De Niro Fakes Marriage, Gets Punched In 'The Big Wedding' Trailer (Video)

Diane Keaton, Katherine Heigl and Susan Sarandon play a dysfunctional family, with Robin Williams and Amanda Seyfried also starring.

Robert De Niro and Diane Keaton are again plunged into matrimonial chaos -- in the vein of Meet the Parents and Father of the Bride -- as the two topline The Big Wedding as the patriarch and matriarch responsible for a tricky knot-tying.

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In the upcoming comedy, long-divorced Don and Ellie Griffin (De Niro and Keaton) must pretend to still be married when the strictly Catholic biological mother of Don’s adopted son Alejandro – the Narnia series’ Ben Barnes, marrying Amanda Seyfried’s Missy O’Connor – unexpectedly flies in for the wedding. Alejandro’s mother considers divorce a sin, and as Alejandro quips, “now she flies out from Colombia only to find out I’ve been lying about being raised by heathens for the last 15 years -- no offense.” De Niro and Keaton score funny lines, and viewers still perturbed over Killer Elite or New Year’s Eve are in luck -- De Niro receives three blows to the face in the clip.

Completing the tangled family, Susan Sarandon is irascible as Don’s current wife, and Topher Grace and Katherine Heigl play Griffin siblings Lyla and Jared.

And Robin Williams -- in his first live-action film role since 2009’s Old Dogs -- rounds out the ensemble as a glib priest.

Wedding is directed by Justin Zackham, who also wrote the film and 2007’s The Bucket List, and among the executive producers is mogul Avi Lerner, whose production The Expendables 2 will bow months earlier.

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The Big Wedding is due for an Oct. 26 release. Watch the trailer below and comment with your thoughts.