You can use storylines for the same purposes as connected clips (such as creating cutaways, compositing titles and other graphics, and adding sound effects and music).
The unique advantage of storylines is the ability to edit a sequence of connected clips within the context of the other clips in the Timeline. For example, you can add cross dissolve transitions to a series of superimposed titles in a storyline and then adjust the timing of the titles to match clips in the primary storyline. Like connected clips, storylines can contain both video and audio, or they can be video only or audio only. For more information about connected clips, see Connect clips to add cutaway shots, titles, and synchronized sound effects.
You edit storylines using the same methods you use to edit the primary storyline. You can:
Add transitions, titles, effects, and generators: Add effects to a storyline by dragging them or by using any of the standard commands and keyboard shortcuts.
Note: When you apply a transition to a clip connected to the primary storyline, a storyline is automatically created for that clip.
Create split edits: Set separate video and audio start and end points in an individual clip to create split edits (L-cuts and J-cuts) in a storyline.
Create or break apart storylines
You can quickly create storylines from existing connected clips.
Choose Clip > Create Storyline (or press Command-G).
A gray border appears around the clips, indicating a storyline.
Note: If the original connected clips are not contiguous, Final Cut Pro inserts a gap clip to fill the space between the clips.
You can also create a storyline by holding down the G key as you drag a clip to a connected clip so that their edges touch:
To convert a storyline back to its component clips, do one of the following:
Select the storyline (by clicking the gray border), and choose Clip > Break Apart Clip Items (or press Shift-Command-G).
Drag the storyline into the primary storyline.
Select and move storylines
You can select or move entire storylines as if they were standard clips or compound clips. They have the connection properties of connected clips.
To select an entire storyline: Click the gray border of the storyline.
To move a storyline by dragging it: Click the gray border of the storyline, and drag it left or right to connect it to a different point along the primary storyline.
To move a storyline with timecode values or keyboard shortcuts: Use the same techniques you would use with standard clips.
For more information, see Arrange clips in the Timeline.