By Owen Quinn author of the Time Warriors and Zombie Blues
So when the Doctor went to Lake Silencia, a mysterious astronaut rose from the depths and shot him dead. Well, shot him and repeatedly shot him when he began to regenerate. We see him looking back at Rory, Amy and River just as the familiar golden glow of regeneration begins to consume him. Well, he solved that particular mystery only to be poisoned by a newly regenerated River Song. She kisses him with lethal lipstick which prevents the Doctor from regenerating. Our hero is only saved when River fills him with regeneration energy in Let’s Kill Hitler to heal himself thus setting her on the path to find the love of her life. While this is all exciting stuff but there’s a slight problem.
As we discovered in the Time of the Doctor, the 11th incarnation was in fact his last body and he spent his days fighting on Trenzalore to protect the town of Christmas. So how then could the Doctor have possibly been about to regenerate when shot at Silencia? But to add even more confusion to the recipe we now know that the Doctor is in fact a being from another dimension who can regenerate an infinite number of times but had his/her memory wiped. Yeah, sometimes you should really leave things alone. Thoughts anyone?
The Time Warriors and Beyond 