Size matters in Up For Love (Un Homme A La Hauteur), a big dollop of soppy French romance in which a decent premise is needlessly compromised by star casting. Laurent Tirard's frothy remake of 2013 Argentinian comedy Corazon de Leon follows a similar path, as divorced lawyer Diane (Virginie Efira) loses her mobile phone and is beguiled by a call from the witty, charming stranger who has found it.

A successful architect with an appetite for life and a friendly word for everyone, Alexandre is also just four feet five inches tall which proves an almost impossible obstacle in the path of true love. Sounds just about plausible, except that Alexandre is played by Oscar-winning six-footer Jean Dujardin with the miracle of modern special-effects deployed to diminish his stature on screen. It is a strange, uncomfortable conceit where you can almost always see the joins. Dujardin is a charismatic actor with a fine comic touch but his presence here just feels wrong. They must have been able to find a suitably diminutive French actor who could have played the part without all the green screen.

Elsewhere, Tirard tends to go for the obvious with little Alexandre constantly being knocked over by a large family dog. The character is also such an all-round great guy that he almost starts to resemble those noble figures played by Sidney Poitier in the 1960s; roles that seemed purposefully crafted to make white audiences feel comfortable with black actors.

Despite all its flaws, however, Up For Love coasts by on the chemistry between Dujardin and a radiant Efira and a smooth soundtrack that stretches from Donna Summer to Anthony And The Johnsons via Chopin.

General release from Fri 5 Aug.