this may be the bad episode of st. the script seem muddle and the science seem plausible initially ( identical particle of matter and anti matter do annihilate and produce radiation and however human body be not particle ) until we see kirk in the anti matter universe . the instant his skin make of matter contact the anti matter atmosphere there would have be a big bang . the acting by robert brown a the mad ( matter ) lazarus be over the top by even my standard ( i consider shatner an excellent actor ) although his sane twin be do much well . a for the plus there be the lovely janet maclachlan a a lt. in charge of the dilithium crystal . her role do however seem almost a if it be insert by the producer a an afterthought . but the sentiment behind it be very much appreciate ( although it be already be cover by nichelle nichols still never too much of a good thing ) .