Over a lifetime of so many memorable and career-defining roles, Sir Patrick Stewart has left indelible footprints across entertainment for decades. From the Enterprise and X-Men to the House of Atreides, Stewart has fans in all corners. But one of his longest-lasting roles, and one of his favorites, is one where he doesn’t physically appear at all -- American Dad! If the saying never meet your heroes is true, don’t tell that to Seth MacFarlane. Because the chance to work with one of his all-time favorite actors, instantly became one of his best decisions – and one of the TV viewers' best rewards.

Stewart plays the wildly inappropriate CIA Deputy Director Avery Bullock. Stewart puts it best, describing Bullock as “an obnoxious, loud, opinionated, vulgar-minded, self-obsessed character.” Bullock embodies the opposite of what comes to mind when most people think of the English icon. In fact, that is part of why Stewart relishes the character, saying, “ It has given me as much pleasure as almost anything in my career.”

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Stan & Avery in dog suits

Seth MacFarlane has made no secret of his love for Star Trek -- particularly The Next Generation. One only needs to watch his live-action sci-fi show, The Orville, to see how that love translated onto the screen. So, when he was creating American Dad! in the early 2000s, he went straight to one of his TV heroes. Stewart, thankfully, didn’t hesitate and jumped on board.

The key to Stewart’s bankability is the way he reaches out through his characters and connects with audiences. His Shakespearean theatrical background fuels his ability to swing wildly between roles. He can inhabit these fictional personas, without letting viewers get distracted by his other famous characters poking out from underneath. From the Civil War to a racist monster, he's believable. This is why when MacFarlane was creating American Dad! he only had one man in mind for the job at the C.I.A.

What helps make American Dad! stand out from other MacFarlane shows, like Family Guy or The Cleveland Show, is the way it approaches stories and characters. With more linear narratives and straightforward plots, the stories rely more on the characters' personalities for humor than heavy amounts of transitional scene gags and non-sequitur's.

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The more traditional story-telling format has helped Stewart embody his Bullock character. After 18 seasons (with a 19th still to come), it has been one of the longest-lasting roles of Stewart's career. He credits the show-runners and MacFarlane for letting him be free playing Avery Bullock the way he chooses. Stewart says there has only been a couple of times he had concerns with saying what was in the script, only to be pleasantly surprised by everyone willing to work around it and find a better way. That kind of creative collaboration is something Stewart credits for his successful tenure, and comfort, doing the show.

MacFarlane came full circle with his love for Gene Roddenberry’s space epic, after making a few guest appearances on the TV series Star Trek: Enterprise. In turn, he gave one of his Star Trek heroes a chance to appear in one of his shows. While American Dad! might seem like the last place you’d find Sir Patrick Stewart, for the acting legend, there is nowhere else he’d rather be.

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