I have read some crime novel and movies as well. Also in Japan where I live, the kind of topic is popular because not only novel and movie but also there are some famous comics which main theme is crime.
I guess there are 3 factos why the works related to crime attract a lot of people and I would dig deeply into each factor below.
There is a space to guess who the criminal is.
That is the important factor to attract the audience. In case of a action movies, we just follow the stories the director created. Of course some audience will guess what will happe in next scene but mainly audience is passive when watching it. While we have some space to guess who criminal is in the crime novel and movie. It can be said that we can “ join “ into the story while using our brain and it will be exciting experience.
The crime fiction has “ reality “.
If the story has reality which along with their life, audience will be more attracted.
In crime novel, the author describes quite details of their life, which is like pattern of behavior of us. It makes audience feel the incindent happens around you and finally they will be into the story. The audience put themselve into the character in the novel and their emotion will be shaked by happening in the novel.
Nobody knows the ending until they finish read it.
Recently, we can access to many movie in Netflix and it become easier to guess the ending than before. In other words, we get used to same template of movie.
But the crime movie and novel is too complicated to judged eariler point. We need to check the facts one by one and something unexpecred happened. Then some audience would give up guessing who criminal is and try to read it quicker. According to strcuture of the story, the audience will not feel bored until the end of story.
These factors make the crime story more attractive and I feel I want to read it too after describing the feature of crime novel and movie. 
I have  
read
  some
  crime
  novel
 and  
movies
  as well
.  
Also
 in Japan where I  
live
, the kind of topic is popular  
because
 not  
only
  novel
 and  
movie
  but
  also
 there are  
some
  famous
 comics which main theme is crime.
I  
guess
 there are 3  
factos
 why the works related to  
crime
 attract  
a lot of
  people
 and I would dig  
deeply
 into each factor below.
There is a space to  
guess
 who the criminal is. 
That is
 the  
important
 factor to attract the  
audience
. In case of  
a
 action  
movies
, we  
just
 follow the  
stories
 the director created.  
Of course
  some
  audience
 will  
guess
 what will  
happe
 in  
next
 scene  
but
  mainly
  audience
 is passive when watching it. While we have  
some
 space to  
guess
  who criminal
 is in the  
crime
  novel
 and  
movie
. It can  
be said
 that we can  
“ 
 join
  “ 
into the  
story
 while using our brain and it will be exciting experience.
The  
crime
 fiction has  
“ 
reality “.
If the  
story
 has reality which along with their life,  
audience
 will be more attracted.
In  
crime
  novel
, the author  
describes
 quite  
details
 of their life, which is like pattern of behavior of us. It  
makes
  audience
 feel the  
incindent
 happens around you and  
finally
 they will be into the  
story
. The  
audience
 put  
themselve
 into the character in the  
novel
 and their emotion will be  
shaked
 by happening in the novel.
Nobody knows the ending until they finish  
read
 it.
Recently, we can access to  
many
  movie
 in Netflix and it  
become
 easier to  
guess
 the ending than  
before
.  
In other words
, we  
get
  used
 to same template of movie. 
But
 the  
crime
  movie
 and  
novel
 is too complicated to judged  
eariler
 point. We need to  
check
 the facts one by one and something  
unexpecred
 happened. Then  
some
  audience
 would give up guessing  
who criminal
 is and try to  
read
 it quicker. According to  
strcuture
 of the  
story
, the  
audience
 will not feel bored until the  
end
 of story.
These factors  
make
 the  
crime
  story
 more attractive and I feel I want to  
read
 it too after describing the feature of  
crime
  novel
 and  
movie
.