Synopsis MI6 's top assassin ( Mark Strong) has a brother . Unfortunately for him , I 's an Inglés football supporter ( Sacha Baron Cohen) from the town of Grimsby. Nobby has everything a man from the poor fishing town of Grimsby Inglés could want - nine children and the MOST attractive girlfriend in northern England ( Rebel Wilson ) . There 's only one thing missing in his life : his little brother , Sebastian . After They Were ADOPTED by different families as children, Nobby spent 28 years searching for him . Upon hearing of His location, Nobby sets off to Reunite With His brother , unaware That is not only an MI6 agent His brother , but he's just uncovered a plot That puts the world in danger . On the run and Wrongfully Accused , Sebastian realizes That if I is going to save the world , I will need the help of Its biggest idiot .