Storylines

There is a basic storyline that can be applied to all basic rom coms, and is found in many popular and mainstream rom coms. Some examples are:

50 first Dates (2004, dir. Peter Segal)

Made of Honour (2008, dir. Paul Weiland)

When Harry Met Sally (1989, dir. Rob Reiner)

Notting Hill (1999, dir. Roger Mitchel)

Ugly Truth (2009, dir. Robert Luketic)

Four Weddings + a funeral
(1994, dir. Mike Newell)

Basic narrative:

• man and woman meet with no romantic feelings for each other- however the filmmakers leave clues that they should have feelings for each other, these characters may bicker and argue throughout the film
•  Whilst the two characters are separated due to a predicament; they realise they have feelings for each other
• One character will attempt to find the other and declare their love in some sort of grand gesture that makes references to previous parts of the film

This narrative ties into Todorov's theory of equilibrium.

• The equilibrium is the two characters not liking each other, 
• then a disruption will happen, the details of which will vary on the film, but often a disagreement or a secret will surface. 
• But ultimately, the final equilibrium is the happy ending. 

Putting this into the context of a film such as When Harry met Sally: they meet, aren't even friends, and continue meeting and becoming friends; this is the equilibrium. The disruption occurs when they have sex and separate from seeing each other, which is where they discover they have feelings for one another. Then the grand gesture on New Years where they declare their love for each other.

However I think the films that simply stick to this storyline, can be quite boring. Some of the more interesting rom coms have another aspect within the storyline of the film. These examples would be:
Scott Pilgrim vs the World (2010, dir. Edgar Wright)

Easy A (2010, dir. Will Gluck)

(500) Days of Summer (2009, dir. Marc Webb)

Scott Pilgrim, is a hybrid of a romantic comedy with the action genre. This does mean the plot line is more of that of an action film opposed to a rom com plot line, where 'getting the girl' is seen as the ultimate goal. Choosing this technique would be going against conventions as not many films use a typical plot line from another genre.

Easy A is a less obvious hybrid however the typical rom com storyline is still more of a sub plot to the actual storyline. This may because Easy A is aimed at teenagers and therefore the majority of the plot is centred around High School and 'surviving' High School. making it a typical 'teen movie'. But also in Easy A, the main plot line is centred around unconventional romance too, making many ties with 'The Scarlett Letter' by Hester Prynne.

(500) Days of Summer is a hybrid of a rom com and a drama. This may be why it has a unique storyline also; however, it is hard to summarise the storyline in (500) Days of Summer, as it is shown in a non-linear sequence, skipping between certain days whilst Tom and Summer are in love. Another difference about (500) Days of Summer and typical rom coms, is that the two main characters in the film, don't end up together, which is used more often in drama films. This film is still seen as mainly a rom com, and with that, has targeted a more niche audience.

So, in conclusion from analysing these three films, perhaps adding elements of another genre may make the film more interesting, as it may be a combination not done before; however there are also many successful rom coms that simply use the traditional storyline.

http://www.filmbug.com/dictionary/romantic-comedies.php