In an appearance on the Late Show with David Letterman last night to promote his new film This is 40, comedian Albert Brooks came clean about something many of us wonder when celebrities appear on talk shows: Are any of the interviews actually impromptu? According to Brooks, not at all - and he has no problem admitting that, when phoned by producers asking for funny anecdotes he'd like to discuss on the show, he just made shit up because he had nothing interesting and actually real to tell them.

Problem is, he also forgot all about what he told the producers. As can be expected, what followed - a purely fictional anecdote about how he once shot a guy at Wal-Mart - is pure gold.

You can check out the video above.

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[via Splitsider]