Here's a link to the Masterpiece presentation. I recommend it:
http://www.pbs.org/wgbh/masterpiece/forsyte/
I also have to make a pitch for the one section of the mini-series that improved upon Galsworthy's presentation.
We all know that Soames is obsessed with Irene and that he refuses to take no for an answer. In fact, Soames does not give Irene any time to meet another man.
However, during his siege of Irene, there was a period of time when they did not see each other. Perhaps, Soames' will weakened then. As often happens, they accidentally ran into each other. They met at the Victorian resort of Bath.
In both the novel and the mini-series, Irene is cordial to Soames as one would be with someone one hasn't seen in a long time. I'm certain she felt his pursuit had died out and that she could simply regard him as an acquaintance.
In the drama, they are shown talking together in one of the public spaces. Soames looks about the room and sees another couple. The others lean in toward each other and the man holds the woman's hand and occasionally kisses it. They are smiling and there is an element of sexual excitement about them.
Of course, Soames completely fails to realize that these other people are "on the same page," that they mutually respond to each other in a positive way. Soames takes Irene's hand and kisses it. She is so upset that she leaves.
Throughout the drama, Soames is depicted as professionally competent but emotionally and socially at sea.
Damian Lewis' performance is amazing. Lewis, now 39, played the older, tightly wound Soames who is completely unlike his own contemporary, easy going self.