After returning from their honeymoon, a newly-wed couple's relationship is put to the test when their respective ex-lovers reappears and tries to 'steal' them back.
Operation: Homewreck
Operation: Homewreck
How about this: "A newly wed couple's relationship is put to the test when their respective ex-lovers reappear and try to 'steal' them back." You have a couple of plural words that should be singular.