Title sequences can take a variety of forms, incorporating different elements. A song may summarize the backstory or premise of the series, such as for "The Brady Bunch", "The Beverly Hillbillies", or "Mister Ed". Less commonly, a voice-over may serve the same function, as for "", "Quantum Leap", or "The Twilight Zone". Often a song will more generally set the theme of the series, such as for "WKRP in Cincinnati", "Cheers", or "All in the Family". An instrumental piece may be used the same way, as for "Taxi", "The Bob Newhart Show", or "Dallas". A title sequence will at some point badge the show with a typographic logo. Visuals may be used to quickly present the backstory, as in "I Dream of Jeannie" or "Gilligan's Island". Because it is produced at the outset of a series, the sequence will usually include visuals taken from early episodes already shot when it was prepared. Short clips of key characters may be used to introduce them and to credit the actors playing them, as with "The Love Boat". In and around these elements may be other footage depicting the setting, or examples of scenes common to the show (e.g. car chases for a police drama, household activities for a sitcom, singing and dancing for a variety show).