The very best moments in every commercial I’ve ever written were improvised. It might be an ad libbed line of dialogue, a character’s walk, or something as small as a gesture.

Even when I’ve been living with a script for months and think I’ve got a character all worked out in my brain, a great actor will add his or her own inflection, changing the timbre of the lines and bringing them to life in a way I never imagined. They’ll play with the words on the page, adding something fresh in the moment.

What’s more, no two takes are ever the same. So even when an actor does something amazing, if you try to recreate it, it doesn’t work. There’s something about spontaneity that’s raw and just a little bit dangerous – which is why I like to film rehearsals. More times than not, especially with comedy, the genius take is the very first one, before everyone gets too polished.

That’s the magic of improvisation.

Watching these great movie moments reminds me that a great story is about ultimately great – and believable – characters.

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