Who is Walter Mitty?

WALTER MITTY is nothing special; Inept at many things, even in simple mechanical tasks.
He can't drive well and he can't remember things well.
For his failings, he gets bossed around and laughed at by his wife and people around him.

However, he has his own "secret life" where he turns into a great man and a hero...

In his imagination, Mitty becomes a commander of the Navy Hydroplane, a famous surgeon who saves the life of his "millionaire banker" patient, a bold crack shot, a heroic British pilot, and a brave man being shot by the firing squad. Here, he is able to do anything that he desires to do.

The goal of Mitty's "secret life" is to be a masculine, brave, intelligent, and heroic man who is completely different from the REAL Walter Mitty.

Full of dissatisfaction and incapabilities in reality, Mitty not only finds a way to escape  from the  mundane life, but sets up his identity as a great man.