“We started talking in terms of redemption,” says Whedon. “We realized, while Buffy is about the hero’s journey — that ‘becoming the person you are’ that happens in adolescence — Angel is about dealing with the person you’ve been.” Or, as co-creator Greenwalt, 69, puts it: “Buffy has this wonderful purpose and fights evil, but still wants to go to the prom and get the right dress. Angel is a much darker and, in a sense, more complex character.”

David Greenwalt will deliver a keynote speech at MIP Cancun this month. He joins Roy Ashton, head of TV lit and packaging at The Gersh…