“pongothedalek” has caught some much better video than the last clips we saw of the filming from Cardiff Bay.
This time you get to see Freema as Martha Jones really close-up (as well as the Doctor and Captain Jack). There are some fantastic moments where she laughs near the end and Russell T. Davies also appears for a bit.
wow! doctor laughs wierd when he gasps
cant wait till 31 March! 
Why Doctor and Martha laugh to Capt. Jack?
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The thing that the Doctor is Sonic Screwdrivering is Jacks “Rift Manipulator, which he had when he used to be a Time Agent,he used it to get back to the 21st century but it went wrong and he ended up in 1880 and the rift manipulator was burned out, so he had to wait for the doctor, using the doctors hand that was cut of during the christmas invasion as a sign of when he was coming to refuel at the rift in cardiff.
In an interview with John Barrowman the Doctor and Martha ARE laughing at Jack goin down to the Torchwood base on the lift. I reckon it wasn’t filmed on that particular day because of the special effects needed but hopefully you will see it.
It’s probably Jack returning to Torchwood at the end of the episode so he can star in Series 2.
Yeahh but can i just point out that i was actually there that day.
And i got Russel T Davies’ autograph.
And about 50 videos & pictures of my phone of the whole thing.
But John & David rather selfishly sprinted across the plass to get away from any fans,
I could say that Freema did the same but instead she just sort of disappeared into thin air and that was the last that anyone saw of her.