There’s only one way to explain just how fun, carefree, and cool a character is: a Hawaiian shirt. Sunglasses, of course, portray cool pretty well, but if a movie really wants to let the audience know that this guy likes to party (or par-tay) they go Hawaiian shirt. Why spend needless time with exposition, back story, or character development when a shirt will do the job for you? Great for fat characters! The floral pattern deemphasizes beer bellies while emphasizing beer drinking.
Hawaiian shirts in film or television say so much more than just big fat party animal… a lamp shade on head or neon t-shirt under sport’s jacket will say that. The Hawaiian shirt is the unexpected party animal. It’s the “Look out for this guy, he’s not your typical [insert unfun occupation].” So, a tax accountant in a Hawaiian shirt means look out for that guy, he’s craaaaaaazy… this is a guy who enjoys long division and a cold pina colada. This is a guy who marches to a different drummer, and that drum might be calypso.
Thomas Magnum (Magnum, PI)
Not just a Detective, a Detective who likes to have fun

Mustache + Hawaiian Shirt = (No, not Gay Porn Star) One Bad Ass that likes to Party
Tom Selleck practically originated Hawaiian shirt good times, before Selleck Aloha shirts simply meant limbo and roasted pig. He changed it to sports cars and intrigue. Notice how his Hawaiian shirt is tucked in, it let’s you know that yeah, Magnum likes to get down, but Magnum likes to wear tight ass jeans, too.
Magnum, PI also has one of the few legitimate excuses for a Hawaiian shirt as it actually took place in Hawaii.
Chadwick Gates (Blue Hawaii)
Not just a surfing GI singer, a surfing GI singer who likes to have fun

Even Elvis turned to the magic of the Hawaiian shirt.
Chunk (Goonies)
Not just a fat kid, a fat kid who likes to have fun

Every fat kid movie has a fat kid who wears Hawaiian shirts. In cinema, it’s the only way to tell the fat kids who are outcasts from the fat kids who have friends.
Freddy Shoop (Summer School)
Not just a Gym Teacher, a Gym Teacher who likes to have fun

Mark Harmon is so cool even his dog is cool. If your teacher is wearing a Hawaiian shirt and his dog wears sunglasses, you know your summer school is going to be a breeze.
Tony Montana (Scarface)
Not just a drug dealer, a drug dealer who likes to have fun

Say hello to my Hawaiian shirt! Not only does a Hawaiian shirt let you know that Tony has a good time, but it let’s you know he’s damn good at having a good time because only the top gangster in town can pull off a Hawaiian shirt.
Quagmire (Family Guy)
Not just a sex addict, a sex addict that likes to have fun

Sex addict in a Hawaiian shirt is like a double sex addict, it immediately let’s you know just how depraved Quagmire is.
John Candy (Everything)
Not just your Uncle/Dad/Salesmen, your Uncle/Dad/Salesman who likes to have fun

Fun is proportional to Fat times Hawaiian meaning true excess can only be expressed through total gluttony. If Hawaiian shirts are for big fat party animals, Hawaiian shirts are for John Candy. He was the Caligula of 80’s comedies, he laughed harder, he ate harder, and he Hawaiian shirted harder than all the rest.
Follow up:
Bonus Hawaiian Shirt!
Bruce Campbell Doll

How many b-list stars can pull off a Hawaiian shirt in Action figure mode? One: Bruce Campbell. When setting up My Name is Bruce, they went for Bruce Campbell down-and-out actor living in a trailer, but he’s still chock full of Bruce Campbell goodness. A Hawaiian shirt was really the only wardrobe option.
Oh doesn’t the creepy coroner on Dexter also wear Hawaiian shirts?