To see a submarine in your dream indicates that you are cautiously exploring your emotions and subconscious feelings. You are guarded about certain emotional issues. Alternatively, the submarine indicates that you need to adapt a different perspective and new understanding of an issue. The submarine is a metaphor that you need to get down to the core of some situation or problem.
Submarine (2011) -- similar to the effect in The Graduate, this film contrasts the individual in the frame alone vís-a-vís with the love interest; often created by same or similar shot, once alone, again with love interest, a third time alone.