UK groups that investigate extraterrestrial life What are some UK based groups that research astrobiology, especially the chance of extraterrestrial intelligence?
Extraterrestial intelligence is a hard research topic as the search for evidence is not straight forward in any way. The search for intelligent life as far as I know is limited to observations in radio and for that you want to see if any SETI members are UK based.

However if you're more into astrobiology in general you might wanna look up the UK Centre for Astrobiology which is based in Edinburgh. I don't know any of the faculty but I do know that they are hosting a meeting for early career scientists in 2017. There are also some smaller research groups based in the UK but you might wanna check out the specific research aim for these (e.g. the group at Imperial College in London is focused on Mars) as it might not be the area within astrobiology that interests you the most. 

There is also Mark Burchell who is a professor at the University of Kent. His group did some exciting work on Panspermia (the idea of life travelling through space) that I happened to read earlier this year. Note that this is focused on microorganisms so this is probably as far from "intelligence" that it gets.

But you can try to look up departments at different universities. You probably want to look under astronomy or sometimes physical or Earth science as the research aims of some groups put them more in e.g. Earth science than actual astronomy. Sometimes you can also find smaller groups under biology or life science.