Complex sentence: Frankie meets with his friend Sean, who is enjoying a peaceful life and has secured a large fishing boat, in which they will sail back to Ireland with the missiles, calling it the "Irish Republican Navy".
Split into simpler sentences: Frankie meets with his friend Sean, who is enjoying a peaceful life and has secured a large fishing boat. With the help of the boat they will sail back to Ireland with the missiles, calling it the "Irish Republican Navy".