Up in heaven after the Archangel Gabriel and Lord Beelzebub fell in love with each other and went off to live on another planet...or something, heaven needed someone. The Metatron tells Aziraphale that since Gabriel hadn’t worked out as the First Principality of Heaven, there is a space available. He suggests that Aziraphale would be perfect for the job. Aziraphale is hesitant at first but then the Metatron promises that since Aziraphale will be able to appoint whomever he likes, he will be able to restore Crowley as an angel.

Crowley didn't take it very well. Long story short, Crowley ended up giving Aziraphale a kiss goodbye before departing. It the angel on the inside, losing his best friend like that while dealing with confusion on his feelings for him.

While up in heaven, Muriel on Earth took care of his bookshop, Aziraphale sighed to himself before hearing a noise, like a whirring noise.

Aziraphale - "Now what...?"

He looked around before seeing a blue police box materializing on the floor. The angel stared in confusion before a man opened the door. He looked.... almost identical to Crowley, except his hair was brunette and his eyes were brown.

Aziraphale - "Crowley?"

The man looked around dthe area in confusion before looking at Aziraphale with a raised eyebrow and a small chuckle.

14th Doctor - "Oh I'm not... Crowley? I'm the Doctor."

Aziraphale paused and looked at the supposed "doctor" before speaking again.

Aziraphale - "Uh...Doctor who?"

14th Doctor - "Exactly. So I might have accidentally came to the wrong place. TARDIS seems to have brought me to... wherever this place is instead of back to Donna's house."

The 14th Doctor sighed and glanced to the side as he realized Donna wouldn't be too happy to hear that he went off on an adventure with the TARDIS without even offering.