Right up until the show actually makes its debut on ABC, it seems we'll have to use the law of subtractions in figuring out the plot and characters of Marvel's 'S.H.I.E.L.D.' TV series. We know for instance, that it won't feature a resurrected fan-favorite Agent Coulson, or incorporate its 'Avengers' counterparts in any consistent way, but what can we expect? Well, get ready to cross another name off the list as 'Item 47' star Lizzy Caplan won't be part of the proceedings either.

Courtesy of SuperHeroHype!, we've just received another nugget of detail on ABC's forthcoming 'S.H.I.E.L.D.' TV series, albeit a disappointing one. Despite her involvement with 'The Avengers' one-shot story 'Item 47,' and potential inclusion into the larger Marvel cinematic universe, former 'Party Down' star Lizzy Caplan has confirmed that she won't be a part of 'S.H.I.E.L.D.'

Speaking at a press conference for her new film '3, 2, 1... Frankie Goes Boom,' Caplan touted upcoming Showtime venture 'Masters of Sex' to preclude her involvement, clarifying "I have my own show so I will not be a regular on the Marvel 'S.H.I.E.L.D.' show. But I'm glad people are so excited about that. I think it's a good idea... Maybe I could do some little thing." Debuting next year, 'Masters of Sex' stars Caplan and Michael Sheen as real-life figures Virginia Johnson and WIlliam Masters, human sexuality researchers in the 1950s.

Of course, that isn't to say that her 'Item 47' co-star Jesse Bradford might not appear in a 'S.H.I.E.L.D.' TV series, provided 'Guys With Kids' doesn't preclude his involvement (hint: it won't). There's also Maximiliano Hernandez, known for playing Agent Jasper Sitwell in the short as well as previous one-shots with Clark Gregg's Coulson.

What say you? Would you like to have seen Lizzy Caplan take an integral role in the 'S.H.I.E.L.D.' TV series?  At this point, who would you like to see the series focus on? Give us your picks in the comments!

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