The ending line...spoiler

His microscope was in the box. Lee was with him in spirit.

That was the best line in the whole movie, imho. Lee was his strength; she believed in him and his ability when he began to doubt it himself, and he knew she would have supported him in his bid to go into research with Terry. In effect, he was taking her spirit along with him. That great ending line and the tight shot with Colman and his bright eager face, to me, made the whole film.