I decided to wait until I'd listened to the TW play a second time, and had a chance to think about it too, before posting a detailed reaction to it.
The play was definitely set after TW 2.13 but before DW 4.13. It was recorded in March and I think (I've not seen the latest issue of TW Magazine to confirm this) it was recorded before they filmed "The Stolen Earth" and "Journey's End", or around the same time.
I laughed at Jack's comment on hearing Martha on his phone: "Suddenly outside a tacky nightclub, the voice of a nightingale." This is clearly a running joke now between Jack and Martha, and I love how it says so much about the two of them and their relationship. Martha doesn't even comment on it - I think she enjoys sharing the level of affection with Jack that's implied by him teasing her in that way.
It was good to know that Martha went to Tosh and Owen's funeral service.
I thought Gwen and Ianto were calling each other "darling" in a very unconvincing way - which actually worked perfectly in the situation.
It was nice to hear that Julia Swales (Martha's friend from Smith and Jones) was also working at CERN. Given Dr Oliver Harrington was Martha's boss at CERN, I'm seeing this as further confirmation that the story is set before 4.12/4.13 since Martha was over in NY then. I'm guessing that they moved her onto Project Indigo after the business at CERN.
I was amused by Jack introducting himself to Professor Johnson before Ianto could introduce himself - there goes Jack, automatically playing the leader even though he's meant to be undercover.
I was also amused by Ianto telling Dr Harrington he knew what it was like to work underground, cut off from the outside world.
I wondered if Martha's comments about Dr Harrington working all the time since he'd lost his wife were aimed particularly at Jack. He strikes me as the sort who would throw himself into his work after losing someone, and it seemed to me that S2 showed that he was very close to both Tosh and Owen, if in different ways.
Interesting to know that Owen was working on the Bekaran Deep Scanner before he died, just as Tosh was working on the Time Lock program for the Hub.
I thought it was interesting that Jack talks about death following Torchwood, and particularly following him, around. How they try to cheat it, but no one escapes except him. He reminded me of the Doctor at that point - which isn't surprising given both men are continually reminded of the brevity of human life. I wasn't surprised that he blamed himself for not being able to save Tosh and Owen, and that he blamed himself for recruiting them and then getting them killed. It was also unsurprising that he feels that he has to look after Gwen and Ianto now.
I liked the emotional continuity between this play and Exit Wounds - the way that Martha asks Jack and Gwen if they're okay, after losing Tosh and Owen. I love her natural empathy and healing nature coming to the fore here, and the fact that she understands Gwen's survivor's guilt.
I laughed at Martha wishing for a sonic screwdriver so that she can break into the building where the missing people are hidden away. And at Ianto contacting Gwen to tell her his bicycle's got a bell!
Martha's "Well make her!" comment to Jack when he says that Professor Johnson says she can't shut down the Collider made me laugh - she sounded very Doctor-ish at that point, and Jack's laconic "Never thought of that" was also amusing.
I wondered how Martha felt when Oliver pulled a gun on her when he found her in the building surrounded by the glowing people, and then he threatened to shoot her. She didn't sound too panicked - more determined to try to reach him.
I thought it was interesting that the "ghost" told Gwen that Jack doesn't care about her and Ianto, and I liked the way she didn't believe it. Her comment to Ianto about coffee and Jack waiting at the end of the tunnel, and him loving both Jack and coffee was amusing.
Jack misquotes Professor Henry Higgins (Pygmalion) "By George I think she's got it!" when Professor Johnson realises what's going on.
At the end Ianto quotes four lines of Tennyson's
All Things Will Die, and Jack finishes the verse:
The stream will cease to flow;
The wind will cease to blow;
The clouds will cease to fleet;
The heart will cease to beat;
For all things must die.
I really enjoyed the play - I thought it was interesting, and also daring that Joseph Lidster mixed science and philosophy (the question of what happens to us when we die) together in such a way. It was also really good to have some proper emotional continuity in Torchwood. And I loved the way that Martha slotted easily and well into the Torchwood team - I do hope we get to see Martha in Torchwood again, at least part time!