Ham-fisted dialogue and clichéd characterizations trump genuine chemistry in The Other Son, a contrived Franco-Israeli drama about two 18-year-olds, an Israeli and a Palestinian, accidentally switched at birth. Joseph Silberg (Jules Sitruk), a wannabe singer, and Yacine Al Bezaaz (Mehdi Dehbi), an aspiring med student, seemingly both assured of their identities, must now adapt to the knowledge that they are not who they thought they were. Lorraine Levy makes the most of a canned hypothetical situation whenever she lets her actors’ body language talk louder than her and co-writer Nathalie Saugeon’s overwrought scenario, as when Yacine’s birth mother, Orith (French siren Emmanuelle Devos), quietly takes her agitated husband Alon’s (Pascal Elbé) drink away from him when he first meets Yacine. But Levy and Saugeon often overtax their already tense drama with loaded plot developments and indelicate dialogue, as when Yacine unconvincingly explains his feelings to Joseph: “I am my worst enemy, but I also must love myself.” A consistently strong cast can’t salvage the scene in which Joseph breaks the ice with his biological family by singing with them at dinner. The shocked look on Saïd Al Bezaaz’s (Khalifa Natour) face when Joseph lustily starts in on the song proves how hard Levy and Saugeon worked to force macro-level significance out of a micro-scale story.