I was sure it was the conclusion too.Everybody else had an 'ending' [either a good outcome or a bad one] all except Tony.I hadn't heard anything about another series.I thought it was a satisfactory ending, Tony had now become unbalanced by it all.I presumed that Tony had drawn the figure in the frosty window, as he spent the rest of his life looking for Ollie.Of course, if there is another series, then perhaps Ollie could be alive, but as a stand alone ending, I thought it was a pretty good one.Fantastic drama, but yes, harrowing at times and hard to watch.