Is Douglas henshall leaving primeval

Yes, he left on the 17th July 2009, in Episode 3 of the Third Series of the show, after being shot by his wife Helen ( Juliet Aubrey ) who also left the show at the end of the Third Series after being pushed off a cliff by a Raptor. Thank goodness Helen was killed off! She did nothing for the show whatsoever to improve it. And I suspect the bottom line for Douglas Henshall was either money or an alcohol problem, perhaps. Those last few episodes, he definitely wasn't at his best IMO, and he ROCKED the first couple seasons. In fact, he MADE THE SHOW the first two seasons. Why walk away from that, unless there was a demand unmet for more money or drug/alcohol problems. Logic dictates, anyway.