Walk and talk

Walk and talk is a storytelling-technique used in filmmaking and television production in which a number of characters have a conversation en route. The most basic form of walk and talk involves a walking character that is then joined by another character. On their way to their destinations, the two talk. Variations include interruptions from other characters and walk and talk relay races, in which new characters join the group and one of the original characters leaves the conversation, while the remaining characters continue the walking and talking.

The technique is frequently used as a means of emphasizing how busy the characters are. It suggests that there is so much to do and so little time to do it in that even traveling time must be used to serve additional functions. It also serves the purposes of smoothing transitions from one location to another and adding visual interest to what might otherwise be static "talking heads" sequences. All three Law & Order series have used the technique to this purpose occasionally, plus all three shows in the CSI franchise use this frequently. Moreover, it has been used as a prominent story-enhancer in numerous episodes of The West Wing, The Bill, House M.D., Ugly Betty, and ER.

The Walk and Talk technique is also often used as a way of combining exposition with a visual introduction to major areas (and their locations in relation to one another) that will be used in a production. Examples of this can be seen in both film (the opening conversation between Mal and Simon in Serenity) and television (the similar conversation between Sinclair and Lyta in the pilot episode of Babylon 5, "The Gathering"). This use of the technique is regularly seen in opening scenes in the UK series Hollyoaks as a way of recapping current story lines and showing how the plot streams interrelate with the characters.

...
Wikipedia