Let's face it, there isn't really much point to this. It's just a way of getting a whole lotta Companions together in one place, really.
#4: The Diary
Susan found the Diary tucked away between two large and very dull-looking books in the Library. Sliding it out, she saw it was a slim volume, with a dark-blue cover that matched the exterior of the TARDIS, and the word "DIARY" embossed on the front. Opening it, she saw it was empty – just page after page of blank, cream-coloured paper.
Grandfather was busy in the control room, so Susan took the little book back to her room. Sitting on her bed, she started to write. About the things she and Grandfather had seen, about the parents she didn't have any more, about everything really. When she finished writing, she had a strange feeling – that she shouldn't keep the book, but instead leave it somewhere for someone else to find. Turning to the front page, she wrote her name on the inside of the front cover. Then she took it to the first room she came across – the lab – and hid it at the bottom of a drawer.
--
Adric had been working on an experiment in the lab when he found the diary. He had simply reached into a drawer to find an extra clamp, and his fingers had found the diary's smooth cover instead. When the experiment was over, he took it back to his room. There was only one entry, and a name written on the inside – Susan.
He wrote an entry of his own, feeling that it was the right thing to do, then added his name underneath Susan's, before finding a place for it in the medical bay.
--
Ace found the diary in a first-aid kit in the medical bay. When she had added her own entry and written her name after Adric's, she hid it in the kitchen.
--
Rose found the diary next, and when it was her turn to hide it she put it in the pocket of a coat hanging up in the TARDIS' extensive wardrobe.
--
When Jack's turn came, he put the diary in the ship's storage cupboard, where the Doctor kept a variety of tools and random pieces of memorabilia.
--
The Doctor had sent Martha looking for some piece of equipment that he (apparently) desperately needed, and she was searching through a very disorganised storage room to find it. As she was on her way out, she noticed the diary poking out of one of the boxes, and picked it up.
In a quiet moment later on, she opened the book. The first thing she noticed was the list of names, all in different handwriting, down the inside cover. The first was Susan, the last was Jack, and there were maybe a dozen names in between. Martha spent that night reading the entries… getting an idea of how the Doctor's old companions had thought and felt.
See that review button down there?
It wants to be pressed. So press it, or I'll send Daleks after you.