The main event was Time Fracture, an 'immersive adventure' in a warehouse just off Oxford Street.
I am not allowed to tell you anything about the Time Fracture, which definitely doesn't exist (what's a Time Fracture?).
Our group was ushered into UNIT Headquarters as volunteers sent by the Doctor, who was unable to attend in person. After a briefing, an emergency and a message from the Doctor, we passed through the Time Fracture in the hope of fixing it.
At this point everyone had a little individual adventure of their own with one of the various aliens and historic figures who were wandering about. Hannah and I found ourselves in the company of an employee from the starship ZZ1, who needed our help finding the combination to her safe. This involved lots of running in and out of other people's stories. The safe contained a ticket, and when we later found ourselves on board ZZ1 headed to Gallifrey, I was able to present it to the alien singer and ask her to dedicate a song to me. A wonderful prize!
There was some business with the High Council of the Time Lords on Gallifrey, then we saved the universe. I loved the whole thing, and was moved by the final message from the Doctor thanking us and telling us all to have a brilliant life: "Spoiler - I know you will."
Then we exited via the gift shop.
Sunday was a BFI screening of City of Death, a Fourth Doctor adventure set (and filmed!) in Paris, written by Douglas Adams, with Julian Glover as the bad guy and a cameo by John Cleese. It's just as much fun as that sounds.
We were treated to some special features from the upcoming box set, and to some special guests, including Julian Glover. It was especially lovely to hear everyone's memories of working with Douglas.
Afterwards we went to the bar, where I made some lovely new Whovian friends.