Without clicking on any emails in the list.
Click on View tab.
Click on Reading Pane and in the drop-down menu, click Off.
With the reading pane off, right click once on an email you want to veiw.
In the drop-down menu, select Properties
Click on the Details tab.
Click on the Message Source... button.
Here it'll open in a notepad-like viewer. Below the email headers will be the message body of the email.